F 

76G 
S3 


ON  THE 


OF  THE 


EOCENE    OF     WYOMING, 


BY  EDWARD  D.  .COPE. 

L.  -y 


(Read  before  the  American  Philosophical  Society,  February  21,  1873.) 


m/f 


ON  THE   SHORT  FOOTED  UNGULATA  OF  THE  EOCENE  OF 

WYOMING. 

BY  EDWARD  D.  COPE. 

(Head  before  the  American  Philosophical  Society,  Feb.  2lst,  1873.) 

In  no  group  of  Mammalia  have  the  determinations  of  palaeontology 
been  more  significant  than  in  the  Ungulata.  Here,  in  an  especial  manner, 
the  anticipations  of  science  have  been  realized,  in  the  filling  up  of  the 
numerous  gaps  in  the  series  of  living  forms.  Here  especially  is  it  evi- 
dent, that  the  existing  fauna  is  but  a  fragment,  and  that  the  faunae  of 
the  past,  as  we  know  them  to-day,  are  but  the  precursors  of  what  we  may 
bring  to  light  to-morrow. 

The  primary  range  of  variation  in  the  structure  of  the  Ungulata,  has 
been  generally  admitted  by  zoologists  to  be  found  in  the  structure  of  the 
limbs  and  feet.  Three  most  prominent  types  have  been  distinguished  on 
this  basis,  viz.  :  the  Artiodactyla,  Perissodactyla  and  the  Proboscidia  : 
with  some  of  the  lesser  importance,  those  of  the  Toxodontia  and  Hyra- 
coidea*  If  we  direct  our  attention  to  the  detailed  structure  of  the  feet, 
or  of  the  teeth,  each  division  offers  its  own  range  of  variation  ;  witness 
in  the  Artiodactyles  the  differences  between  the  Ruminantia  and  Omni- 
vora,  and  in  Perissodactyla,  between  Equus  and  RMnocerus.  In  either 
order  canines  and  incisors  may  be  present  or  absent,  and  molars  assume 
a  great  variety  of  patterns  of  enamel  plication.  The  toes  in  the  latter 
order  may  vary  from  four  to  one.  Nevertheless,  the  most  diverse  genera 
are  bound  together  by  intermediate  forms,  often  extinct.  Connecting 
Omnivora  and  Ruminantia  come  Oreodon.  Merycopotamus,  Tragulus,  etc. 
In  Perissodactyla,  Anchitherium,  Palceosyops,  etc.,  connect  the  extremes. 

The  Proboscidians  have,  on  the  other  hand,  remained  until  recently  an 
isolated  group  with  but  few  representatives,  hence  its  definition  as  an 
order,  has  been  more  or  less  obscured  by  characters  of  a  special  nature, 
drawn  from  the  dentifion,  trunk,  etc.,  which  it  has  been  found  necessary 
to  omit  in  characterizing  the  two  orders  above  mentioned.  These  charac- 
ters are  so  striking  in  their  appearance  as  to  suggest  greater  systematic 
importance  than  belongs  to  them.  Thus  the  trunk  is  not  more  important 
as  a  character  of  the  Proboscidia,  than  it  is  of  the  Perissodactyla,  where 
the  tapir  alone  possesses  it.  Nor  are  the  complex  molars  and  large  tusks 
to  be  regarded  as  a  definition,  for  in  the  Phacochcerus  we  have  molars  as 
compound  as  in  some  mastodons,  huge  canine  teeth  and  no  incisors  below  ; 
characters  very  different  from  many  Artiodactyles.  Nor  can  we  regard 
the  exclusive  union  of  the  astragalus  with  the  navicular  a&  a  final  test,  for 
in  Perissodactyles  the  facet  for  union  with  the  cuboid  may  be  considera- 
ble (RMnocerus}  to  almost  nothing  (Equus}. 

The  occasion  for  this  discussion  is  presented  by  the  discovery  by  the 

*  Vide  Gill,  Arrangement  of  the  Families  of  Mammals,  Smithson,  Misc.,  Coll.,  1872,  No.  230; 
the  best  analysis  of  the  Mammalia  yet  published. 


palaeontologists  of  Haydeii's  geological  surveys  of  1871-2,  of  the  remark- 
able types  Bathmodon,  UintatJierium,  and  Eobasileus.  These  genera  con- 
tradict in  several  particulars  the  characters  usually  assigned  to  the  Pro- 
boscidia, while  they  agree  with  them  in  others,  and  they  thus  present  the 
problem  of  classification,  which  will  ever  recur  so  long  as  additions  to 
our  knowledge  of  the  life  of  the  past  continue  to  be  made.  This  problem 
is  simply  the  question  as  to  what  characters  shall  be  retained  as  definitive 
of  natural  divisions,  on  the  discovery  of  intermediate  forms.  As  our 
system  is  an  expression  of  the  possession  of  structural  characters,  our 
higher  groups  or  orders  are  naturally  expressions  of  the  existence  of  the 
more  comprehensive  characters,  or  those  present  through  the  most  ex- 
tended series  of  species.  Hence  we  believe  them  to  be  also  those  assumed 
earliest  in  time. 

In  the  case  of  the  Ungulata,  the  structure  of  the  feet  seems  to  define 
the  greatest  range  of  the  species.  Thus  the  Artiodactyla  and  Perisso- 
dactyla  are  digitigrade  or  unguligrade,  while  the  Proboscidia  are  nearly 
plantigrade.  The  first  order  exhibits  the  equal  development  of  the  third 
and  fourth  toes  ;  the  second  of  the  third  toe,  while  in  the  Proboscidia  the 
structure  is  like  the  last,  with  more,,  numerous  digits.  But  this  order 
differs  from  both  the  preceding  in  the  relations  of  the  ulna  and  radius. 
In  Artiodactyla  and  Perissodactyla  the  ulna  diminishes  greatly  distally 
and  presents  but  a  small  carpal  articular  surface  obliquely  behind  that  of 
the  much  larger  radius.  In  Proboscidia  the  ulna  presents  the  larger 
articulation  with  the  carpus,  and  the  radius  crosses  it  obliquely,  and  pre- 
sents its  articular  face  alongside  of  the  uliiar. 

The  characters  of  the  three  orders  may  be  thus  stated  : 

PKOBOSCIDIA.  * 

Feet  plantigrade  but  elevated  behind  by  a  plantar  pad.  Toes  nume- 
rous, short,  the  middle  (3d)  largest.  Hind  limb  with  knee  free  from  the 
body  ;  tibia  without  spine  ;  astragalus  flat,  not  produced  anteriorly.  Fore 
limb  with  well  developed  ulna  articulating  extensively  with  the  carpus 
along  side  of  the  smaller  radius,  which  crosses  it  obliquely. 

PERISSODACTYLA. 

Feet  digitigrade,  with  a  hock  joint.  Toes  reduced  in  number,  the  third 
largest.  Hind  limb  with  knee  enclosed  in  integument  of  body  ;  femur 
with  third  trochanter  ;  tibia  with  spine.  Astragalus  with  pulley-shaped 
articular  face  for  tibia  and  anterior  prolongation.  Fore  limb  with  ulna 
reduced,  its  carpal  surface  smaller  than  that  of  the  radius,  which  sup- 
ports the  foot  in  front  of  the  ulna. 

ARTIODACTYLA. 

Feet  digitigrade  or  unguligrade.  Toes  reduced,  the  third  and  fourth 
principally  and  equally  developed.  Hind  limb  with  knee  applied  to  the 
side  of  the  body,  and  elevated  hock ;  femur  without  third  trochanter  ; 

*  These  characters  have  been  mostly  given  by  Prof.  Gill,  1.  c. 


tibia  with  large  spine.  Astragalus  with  both  inferior  and  anterior 
pulley-shaped  surfaces.  Ulna  much  reduced  distally,  behind  the  radius, 
which  includes  almost  the  whole  of  the  carpal  articulation. 

This  arrangement  violates  previous  views  less  than  any  other  that 
would  recognize  the  primary  characters  of  the  Eobasil&us.  The  difficulty 
of  determining  the  limits  of  the  two  first  named  orders,  is  partially 
caused  by  the  fact  that  the  Hyracoidea  present  the  radius  of  the  Proboscidia 
with  the  hind  foot  of  the  Perissodactyla.  These  animals  are,  however, 
well  regarded  as  a  distinct  order.  Whether  all  the  animals  to  be  included 
in  the  Proboscidia  possessed  a  proboscis  or  not,  is  of  secondary  importance. 
It  is  neverthele'ss  highly  probable  that  Loxolophodon  and  Eobasileus  pos- 
sessed one,  and  not  unlikely  that  such  forms  that  approach  still  nearer 
the  tapirs  were  not  without  an  organ  such  as  they  possess,  and  which 
Cuvier  ascribed  to  the  PalcBotheria  and  other  allies. 

The  divisions  of  the  Proboscidia  are  as  follows : 

No  incisors,  nasal  bones  short ;  astragalus  articulating 
with  navicular  only  :  No  third  trochanter Proboscidia  vera. 

No  incisors,  nasal  bones  elongate  ;  astragalus  articu- 
lating with  both  navicular  and  cuboid  :  No  third  tro- 
chanter   Dinocerata . 

Dentition  complete ;  i.  e.  incisors  present ;  ?  nasal 
bones.  Astragalus  articulating  with  both  navicular 
and  cuboid  :  A  rudimental  third  trochanter Pantodonta.. 

These  suborders  present  a  series  of  approaches  to  the  Perissodactyla. 
Thus  the  Dinocerata  agree  with  the  typical  Proboscidia  in  addition  to  the 
above  points,  in  the  posterior  expansion  of  the  scapula,  and  its  apical 
acumination  ;  in  the  very  short  cervical  vertebrae  ;  in  the  flat  carpal 
bones  ;  in  the  absence  of  pit  for  round  ligament  of  the  femur  ;  in  the  flat- 
tened great  trochanter,  contracted  condyles,  and  fissure-like  intercondylar 
fossa  of  the  same  bone.  In  the  longitudinal  crest  of  the  tibia  separating 
glenoid  articular  faces  which  are  on  a  transverse  line.  In  the  short  cal- 
caneum  which  is  wider  than  long,  and  tubercular  on  the  inferior  face. 
In  the  five  digits ;  the  acetabulum  not  separated  by  a  peduncle  from 
the  iliac  plates,  and  the  lack  of  angular  production  of  the  latter  beyond 
the  sacrum.  Also  in  the  three  distinguished  sacral  vertebrae,  as  con- 
trasted with  the  five  closely  coossified  ones  of  the  Rhinocerotidce.  These 
characters  are,  some  of  them,  of  subordinate  value  only. 

The  chief  differences  are  seen  in  the  cranium,  though  here  also  there 
are  important  resemblances.  Thus  in  Loxolopliodon  the  malar  bone  forms 
the  middle  element  of  the  zygomatic  arch,  sending  a  narrow  strip  only  for- 
ward to  the  neighborhood  of  the  lachrymal.  In  Uintatherium,  accord- 
ing to  Marsh,  its  extension  towards  the  side  of  the  face  is  rather  greater, 
but  still  much  less  than  in  Perissodactyla.  The  dentition  is  not  far 
removed  from  that  of  Dinotherium,  and  the  mode  of  succession  of  the 
teeth  was  in  all  probability  similar.  The  premaxillaries  and  nasals  are 


4 

excavated  and  exostosed  for  the  attachment  of  a  trunk  in  LoxolopJwdon. 
The  lateral  and  occipital  crests  of  the  cranium,  though  different  from 
the  enlarged  sinuses  of  the  diploe  of  Elephants,  represent  the  external 
walls  of  this  structure,  and  furnish  a  hint  as  to  its  mode  of  origin,  and 
serve  to  ease  the  transition  to  Perissodactyles. 

The  differences  in  the  cranium  are  consequent  upon  its  anterior  elonga- 
tion, the  nasal  bones  and  premaxillaries  becoming  thus  much  extended. 
The  lachrymal  is  perforated  by  a  small  lachrymal  canal  in  Uintatherium, 
according  to  Marsh,  but  excavated  on  the  margin  only  in  LoxolopJwdon. 
It  is  neither  in  Elephas.  There  is  a  postglenoid  process  more  largely 
developed  than  in  Proboscidia  vera.  Other  differences  of  still  less  import- 
ance are  to  be  seen  in  the  anterior  position  of  the  exterior  nares,  and 
the  presence  of  horns. 

The  Pantodonta  are  represented  by  Bathmodon.  With  a  structure  of 
the  hinder  limb  "nearly  resembling  Eobasileus,  we  have  more  pronounced 
relationships  to  the  Perissodactyles.  The  scapula  has  the  massive 
apical  acuminatiou  of  the  Proboscidia  vera,  and  there  is  no  round  ligament 
of  the  femur  in  some  of  them.  The  astragalus  has  the  same  flattened 
form  seen  in  Uintatherium  and  is  even  less  like  that  of  the  Perissodac- 
'tyla.  The  type  of  molars  and  the  long  compressed  canines  are  similar  to 
those  of  Loxolophodon.  On  the  other  hand,  the  cervical  vertebrae  are 
rather  longer,  and  there  is  a  rudimental  third  trochanter  of  the  femur. 

History,  etc.  I  originally  referred  the  Eobasileidw  to  the  Proboscidia, 
•  on  account  of  the  structure  of  the  limbs,  and  subsequently  stated  a  num- 
ber of  reasons  for  this  conclusion  at  a  meeting  of  the  Academy  Natural 
Sciences  of  Philadelphia,  held  January  14th,  1873  (published  January 
16th).  In'  the  present  paper,  numerous  confirmatory  characters  are 
added.  The  Bathmodontidce  I  have  heretofore  referred  to  the  Perisso- 
dactyla. 

Prof.  Marsh,  in  describing  a  species  of  this  group,  TitanotJierium 
f  anceps  (July,  1871),  compares  it  with  perissodactyle  species,  and  in  de- 
scribing the  tibia  says,  that  it  "at  its  proximal  end,  has  the  femoral  sur- 
faces contiguous,  with  no  prominent  elevation  between  them,  resembling 
in  this  respect  some  of  the  Proboscidea. "  A  few  days  before  the  publi- 
cation of  my  conclusions,  in  a  foot-note  (July  22d,  1872),  he  altered  the 
name  Titanotkerium  to  Mastodon,  indicating  that  he  had  reached  the 
same  opinion.  Shortly  after  (Amer.  Journ.  Sci.  Arts,  Sept.  27th),  he 
altered  his  view,  constructing  a  supposed  new  order  " Dinocerata,"  for 
their  reception. 

As  regards  the  name  of  the  order  here  defined  as  including  the  three 
suborders  above  mentioned,  I  have  preferred  using  one  already  employed 
to  coining  a  new  one.  This  is  the  better  course  also,  if,  as  is  not  unlikely, 
the  distinctions  on  which  it,  as  well  as  the  oiher  two  orders  repose,  shall 
be  broken  down  by  new  discoveries  in  paleontology. 


5 

DlNOCERATA. 

The  genera  of  this*  group  known  to  the  writer  are  four,  which  differ 
as  follow  : 

1.  Nasal  bones  with  flat  horizontal  horn-cores  overhanging  their  apex. 
Cervical  vertebrae  short ;  malar  bone  much  reduced  in 

front Loxolophodon. 

2.  Nasal  bones  with  small  tuberosities. 

Cervical  vertebrae  short Bohasileua. 

Cervical  vertebrae  longer;  the  malar  bone  reaching  maxil- 
lary face Uimatherium. 

3.  Nasal  bones  without  the  anterior  horn-cores. 

Cervicals  ? Megacer-atops. 

The  dentition  of  this  group  requires  special  notice.  Judging  from  the 
relative  sizes  of  the  teeth,  I  have  written  the  molar  series  of  Loxoloplio- 
don  4 — 2,  but  judging  from  the  forms  of  the  crowns,  it  should  be  1 — 5. 
However  this  should  be,  I  have  no  doubt  that  as  in  other  Proboscidia  the 
premolar  and  not  the  molar  series  is  deficient,  and  that  there  are  three 
or  four  true  molars  at  least.  In  a  mandible  found  alone,  which  agrees  in 
size  with  some  species  of  Uintatlierium,  six  molars  are  preserved.  Of 
these  the  posterior  two  display  three  sub-transverse  crests,  of  which  the 
anterior  two  form  a  chevron  with  open  apex  directed  to  the  inside.  An- 
terior to  the  front  crest  is  a  cingular  tubercle.  The  symphyseal  part  of 
the  jaw  is  remarkable  :  it  is  coossified,  exceedingly  compressed,  and 
curved  upwards  so  as  to  resemble  slightly  the  narrow  prow  of  a  South 
Sea  boat.  There  are  two  teeth  on  each  side,  which  are  separated  from 
the  molars  by  a  diastema.  They  are  much  compressed  and  curved  up- 
wards and  forwards,  and  the  anterior  pair  issue  from  the  jaw  in  contact. 
The  crowns  are  lost  in  the  specimen.  The  determination  of  these  teeth 
is  facilitated  by  the  presence  of  the  mental  foramen  below  the  posterior 
one.  This  foramen  issues,  as  is  well  known,  posterior  to  the  canines  in 
all  mammalia,  and  either  below  premolars,  or  the  diastema.  The  two 
teeth  in  our  fossil  will  then  be  premolar  and  canine  respectively,  and  the 
incisors  must  be  regarded  as  wanting.  This  is  in  conformity  with  the 
structure  of  the  upper  jaw,  and  is  rendered  probable  by  the  great  reduc- 
tion of  the  symphysis  of  the  lower  jaw  in  the  species.  It  is  also  suggested 
by  the  almost  universal  tendency  to  reduction  of  the  incisors  seen  in  the 
mammals  of  the  same  extinct  fauna.  In  Bathmodon  and  Palceosyops  the 
canines  are  thrown  into  the  incisor  series  as  in  Ruminantia,  and  in  Palcc- 
osyops  the  outer  incisors  are  much  reduced.  In  several  genera  there  are 
but  two  incisors.  Finally  in  Synoplotherium,  and  probably*in  Anchipho- 
dus,  the  large  inferior  teeth  described  by  Dr.  Leidy  and  myself  as  in- 
cisors and  which  resemble  the  cutters  of  Rodentia,  are  immediately  in 
front  of  the  mental  foramen,  and  bear  the  same  relation  to  it  and  to  the 
premolar  teeth,  as  do  the  canines  of  Palceosyopa  and  other  mammalia. 
Hence  I  believe  these  to  be  canines,  and  that  the  inferior  incisors  are 


wanting.  The  probability  of  the  truth  ol  this  determination  is  increased 
by  the  presence  of  a  small  interval  between  them,  and  by  the  fact  that 
they  oppose  the  canines  of  the  upper  jaw. 

LOXOLOPHODON.     Cope. 

Proceedings  American  Philosophical  Society,  1872,  p.  580,  extra  copies 

published  August  19th  ;  and  p.  488  (Aug.  22d). 

The  cranium  in  this  genus  is  very  elongate  and  compressed.  The 
muzzle  is  posteriorly  roof-shaped,  but  is  anteriorly  concave  and  flattened 
out  into  a  bi-lobed  shovel  which  rises  above  the  extremity  of  the  bone. 
This  extremity  is  subconic,  and  short  and  decurved.  A  second  pair  of 
horn-cores  stands  above  the  orbits  ;  each  one  composed  externally  of  the 
maxillary  bone,  and  internally  of  an  upward  extension  of  the  posterior 
part  of  the  nasal.  Behind  this  horn  the  superior  margin  of  the  temporal 
fossa  sinks,  but  rises  again  at  its  posterior  portion,  probably  above  the 
level  of  the  middle  of  the  parietal  bones.  This  portion  of  the  skull  is 
injured  in  my  only  specimen.  The  occipital  rises  in  a  wall  upwards  from 
the  foramen  magnum,  and  supports,  probably  a  little  in  front  of  the  junc- 
tion with  the  superior  and  inferior  ridges  bounding  the  temporal  fossa,  a 
third  horn  core  on  each  side.  The  base  of  this  core  is  as  stout  as  that 
above  the  orbit,  and  sub-cylindric  in  section.  The  temporal  fossa  has  its 
principal  extent  posterior  to  the  zygomatic  arch,  and  is  in  form  like  a 
trough,  the  inferior  edge  being  recurved  from  the  squamosal  process  to 
the  summit  of  the  occipital  crest.  It  is  narrow  within  the  zygomatic 
arch,  which  is  short,  enclosing  a  space  whose  length  is  less  than  one- 
fourth  that  of  the  cranium. 

The  occipital  bone  extends  but  a  short  distance  on  each  side  of  the 
condyles,  and  is  separated  from  the  mastoid  by  an  irregular  suture, 
which  is  pierced  by  a  large  mastoid  foramen.  On  the  inferior  face  near 
to  each  condyle  and  one-third  the  distance  from  its  inner  extremity,  is  a 
posterior  condyloid  foramen,  isolated  by  a  narrow  bar  from  the  extremity 
of  the  foramen  lacerum  posterius.  The  paramastoid  process  is  repre- 
sented by  a  small  tuberosity,  and  the  mastoid  by  a  rather  larger  one, 
some  distance  anterior  to  it. 

The  meatus  auditorius  opens  upwards  just  below  the  external  ridge  of 
the  temporal  fossa  and  at  a  little  distance  behind  the  post-glenoid  pro- 
cess. Its  canal  contracts  rapidly,  and  extends  upwards  and  backwards 
towards  the  labyrinth.  It  is  separated  from  the  foramen  lacerum  by  but 
a  thin  wall,  and  if  there  was  an  expansion  of  the  cavum  tympam,  it  must 
have  been  exceedingly  small,  owing  to  the  close  approximation  of  the 
mastoid  to  ttie  basi-occipital  and  sphenoid  at  this  point.  The  labyrinth 
is  lodged  in  a  petrous  mass  opposite  the  occipito-mastoid  suture,  and  the 
canals  are  small. 

The  basi-occipital  contracts  anteriorly,  and  with  the  sphenoid  forms  an 
uninterrupted  boundary  of  the  foramen  lacerum.  This  terminates  oppo- 
site to  the  posterior  boundary  of  the  external  meatus.  and  gives  rise  to  a 


wide  shallow  groove  which  extends  anteriorly  between  the  pterygoid 
ala  and  the  postglenoid  process,  and  turning  outwards  round  the  latter, 
grooves  it.  Opposite  to  the  postglenoid  process  and  just  posterior  to  the 
end  of  the  pterygoid  a  small  foramen  enters,  which  is  probably  the  for- 
amen ovale.  Almost  continuous  with  it  is  a  canal  which  pierces  the  base 
of  the  pterygoid  longitudinally,  and  issues  in  an  excavation  of  its  exter- 
nal face  near  the  sphenoid. 

The  pterygoids  are  remarkable  for  their  great  length,  enclosing  as  they 
do  with  the  palatine  processes,  a  deep,  narrow,  trench-like  fossa,  which 
measures  almost  the  entire  length  of  the  zygomatic  fossa.  Processes  of 
the  sphenoid  contribute  to  these  walls  (which  are  thus  double),  and  the 
sphenoid  roof  is  strongly  concave.  The  alisphenoid  is  elongate  antero- 
posteriorly,  and  is  principally  in  contact  superiorly  with  the  frontal;  an- 
teriorly it  has  a  short  suture  with  the  lachrymal.  Almost  its  entire  length 
is  traversed  by  a  shallow  groove  which  terminates  in  a  small  foramen 
opticum,  opposite  to  a  point  marking  the  posterior  third  of  the  zygomatic 
fossa.  The  foramen  rotundum  issues  as  usual  between  the  alisphenoid 
and  the  pterygoid,  but  is'  considerably  anterior,  as  well  as  inferior  to  the 
/.  opticum.  I  cannot  determine  whether  the  orbitosphenoid  is  distinct. 

The  lachrymal  is  a  large  bone  of  a  triangular  outline,  the  shorter 
side  being  inferior.  It  is  entirely  on  the  inner  face  of  the  orbit,  and 
as  in  the  elephant,  separates  the  frontal  and  maxillary  by  its  superior 
prolongation.  Its  inferior  border  is  slightly  notched  in  front  by  the 
large  foramen  infraorbitale  posterius,  and  the  anterior  is  deeply  emargi- 
nate,  passing  behind  the  small/,  lachrymale. 

The  palate  is  remarkable  for  its  length  and  narrowness.  Its  roof  is 
chiefly  composed  of  the  maxillaries,  but  a  very  short  portion  is  formed  by 
the  palatine  plates  of  the  o.  o.  palatina.  These  are  produced  into  a 
median  point  behind  between  the  nares,  and  exteriorly  form  the  inner 
wall  of  the  postnareal  trough  for  a  considerable  distance.  The  maxil- 
laries also  form  the  outer  wall  for  a  short  distance,  being  produced  in  a 
contracted  form  behind  the  molar  teeth.  The  two  bones  enclose  a  small 
foramen  in  this  prolongation,  and  a  larger  one  on  the  anterior  suture  of 
the  palatine,  the  foramen  palatinum.  The  palate  is  deeply  concave 
anteriorly.  There  is  an  elongate  foramen  close  to  the  alveolus  of  the  first 
premolar,  extending  anterior  to  it.  The  premaxillaries  are  longitudinal 
and  separated  anteriorly  for  two-fifths  of  their  length,  by  a  large  foramen 
incisivum,  which  they  do  not  enclose.  They  extend  on  the  side  of  the 
muzzle  into  an  acute  angle  upwards  and  backwards  and  are  prolonged 
forwards  above  the  exterior  nares,  which  the  suture  reaphes  by  an 
abrupt  descent.  The  maxillary  supports  the  malar  on  a  posteriorly 
directed  process  which  reaches  to  the  end  of  the  anterior  third  of  the 
arch  below,  half  that  distance  on  the  side,  and  is  bordered  by  a  narrow 
strip  of  the  malar  on  the  inner  side,  as  far  as  the  anterior  boundary  of 
the  orbit.  The  premaxillaries  do  not  enclose  the  very  large  foramen  in- 
cisivum in  front,  and  are  therefore  deeply  furcate. 


8 

The  dentition  is  I.  0  ;  C.  1  ;  P.  M.  4  ;  M.  2.  The  canine  is  a  tusk  of 
compressed  form  with  anterior  and  posterior  cutting  edges,  and  a  strong 
posterior  curvature.  Its  fang  is  embraced  one-third  by  the  premaxillary 
bone,  and  is  enclosed  in  a  rib-like  swelling  of  the  side  of  the  cranium, 
which  extends  upwards  and  backwards.  The  premolars  are  well  worn, 
and  have  transverse  cordate  surfaces  of  attrition.  These  have  probably 
resulted  from  the  wearing  down  of  a  chevron  of  two  crests  converging 
inwards,  in  some  with  an  inner  tubercle.  On  the  molars  this  crescent  is 
represented  by  a  V,  with  the  apex  inwards  ;  on  the  last,  the  inner  tuber- 
cle is  at  one  side  (the  posterior)  of  the  apex. 

Name. — I  first  applied  the  name  Loxolopliodon  to  this  genus  in  a  short 
paper  published  August  19,  1872,  as  above  cited,  with  a  diagnostic  de- 
scription ;  the  L.  cornutus  was  there  cited  as  the  first  species,  and  is  here 
retained  as  the  type.  I  again  described  it  more  fully  in  a  paper  published 
August  22d,  citing  Eolasileus  (August  20th)  as  a  synonym,  in  which  I 
was  in  error,  as  indicated  by  the  present  paper.  The  same  nomenclature 
was  employed  in  a  paper  read  before  the  American  Association  for  the 
Advancement  of  Science,  held  at  Dubuque,  commencing  August  23,  1872. 

In  the  paper  of  August  22d,  I  regarded  this  genus  as  identical  with 
that  to  which  I  had  previously  (February  16,  1872)  applied  the  name 
Loxolophodon,  and  included  in  it  the  species  there  called  Bathmodon 
(Loxolophodon}  semicinctus,  Cope.  With  further  material  this  appears 
not  to  be  correct ;  the  Bathmodon  semicinctus  belongs  truly  to  that 
genus,  and  is  very  near  to  the  B.  radians,  so  that  the  name  Loxolophodon 
becemes  a  synonym  in  this  connection,  and  may  be  used  again  for  the 
present  genus  without  interference. 

LOXOLOPHODON  CORNUTUS.    Cope. 

Loxolophodon  cornutus,  Cope.  Proceedings  American  Philosophical 
Society,  1872,  p.  580  (August  19th),  1.  c.  1872,  p.  488  (August  22d). 
Eobasileus  cornutus,  Cope,  American  Naturalist,  1872,  p.  774. 

Established  on  the  remains  of  a  single  individual,  which  consist  of  a 
nearly  perfect  cranium,  the  right  scapula  complete,  several  vertebra 
including  the  sacral,  the  first  or  second  rib,  the  pelvis  complete,  and  the 
entire  right  femur  ;  also  probably  the  proximal  end  of  a  radius. 

The  species  is  remarkable  for  the  narrow  form  of  the  cranium,  its 
width  at  the  middle  being  one-fourth  its  length.  A  little  in  front  of  the 
middle,  are  situated  the  horn-cores.  These  diverge,  the  upper  portion 
having  an  outward  curvature.  The  base  of  each  is  triangular  with 
obtuse  angles  in  section,  and  the  inner  angle  is  the  section  of  a  rib-like 
projection  which  extends  across  the  middle  line  to  its  fellow  and  rises 
half  way  up  the  horn-core.  Above  its  rather  abrupt  termination,  the 
core  is  transversely  compressed,  with  oval  obtuse  apex.  The  core 
measures  M.  .240  (9.5  inches)  from  its  base  in  front,  M.  .108  (4.25  inches)  in 
width  at  the  base  behind,  and  .077  (3  inches)  in  diameter  at  the  apex.  A 
slight  swelling  of  the  sides  of  the  muzzle  descends  obliquely  forwards 


9 

from  the  base  of  each  horn,  which  enlarges  below  into  a  prominent  rib, 
which  encloses  the  alveolus  of  the  canine  tusk.  In  front  of  the  horns 
the  muzzle  is  roof-like  ;  anteriorly  it  flattens  out,  and  swells  a  little 
above  the  posterior  end  of  the  nasal  meatus.  In  front  of  this  it  expands 
again,  and  rises  gently  to  the  extremity  of  the  bi-lobed  nasal  shovel,  which 
overhangs  the  premaxillaries,  the  nasal  meatus  and  the  greater  part  of 
the  apex  of  the  nasal  bones.  The  latter  is  short  and  with  a  wide  base  and 
resembles  two  lateral  cones  flattened  together,  their  extremities  obliquely 
truncate  outwards  and  excavated.  The  composition  of  the  upper  surface 
of  the  cranium  is  somewhat  difficult  to  determine,  owing  to  the  injured 
state  of  the  posterior  part.  If  we  regard  the  bone  which  bounds  the 
lachrymal  behind  and  above,  as  frontal,  as  I  did  in  originally  describing 
the  species,  it  gives  an  extraordinary  extent  to  the  nasals,  for  the  com- 
mon suture  of  these  bones  extends  Y-shaped  backwards,  to  a  point 
opposite  to  the  middle  of  the  zygomatic  arches.  It  gives  to  the  nasals 
an  extent  equal  to  that  of  the  frontals  and  parietals  combined.  They 
not  only  support  the  anterior  shovels  but  form  the  inner  half  of  the 
median  horn-cores,  rising  as  high  as  the  tuberosity  above  described.  To 
regard  these  bones  as  frontals  would  involve  the  improbable  peculiarity 
of  their  extending  beyond  the  nareal  orifices,  and  the  terminal  cone  of 
the  nasals  is  not  separated  from  them  by  suture.  The  question  is  decided 
in  favor  of  their  being  nasals,  by  those  bones  as  preserved  in  Eobasileus 
pressicorniSj  Cope,  where  the  shovel  is  represented  by  a  tubercle  only  on 
the  side  of  a  continuous  nasal.  The  immense -length  of  the  snout  in  Loxo- 
loplwn  looks  as  though  the  nasal  bones  had  extended  themselves  for- 
ward, so  as  to  ossify  the  basal  portions  of  an  elephantine  proboscis. 

The  frontals  descend  behind  the  horns,  with  a  very  obtuse  or  rounded 
continuation,  to  the  inner  side  of  the  fossa,  and  without  any  superciliary 
margin.  They  form  with  the  posterior  part  of  the  nasals  a  shallow  me- 
dian basin.  The  suture  with  the  parietals  is  very  indistinct,  but  if  I 
have  truly  discovered  it,  it  forms  another  posteriorly  directed  chevron, 
and  leaves  but  a  narrow  superciliary  portion  of  the  frontals.  Above  the 
postglenoid  processes  the  parietals  rise  again  to  the  transverse  occipital 
crest,  but  to  what  height  is  uncertain.  At  the  mastoid  region,  the 
cranium  widens  a  little,  and  is  excavated  at  the  sides  by  the  temporal 
fossae.  Near  where  the  lateral  and  posterior  crests  join  the  inferior  ridge- 
like  border  of  the  temporal  fossa,  in  front  of  a  position  occupied  by  a 
knob  in  E.  pressicornis,  is  a  strong  horn-core  with  sub-cylindric  base. 
It  stands  obliquely  backwards  towards  the  junction  of  the  inferior 
squamosal  and  transverse  crests,  and  is  connected  to  these  by  an  oblique 
ridge,  one  side  of  which  is  marked  with  irregular,  short,  longitudinal 
rugosities.  At  the  base  of  these  elevations  are  three  sinuses.  This  por- 
tion was  found  close  to  the  skull,  but  separated  from  it,  and  the  precise 
mode  of  its  attachment  has  not  been  discovered  by  actual  fit. 

The  occiput  rises  upwards  for  four  inches  above  the  condyles;  perhaps 
it  displayed  a  posteriorly  sloping  transverse  crest  as  in  E.  pressicorms. 


10 

The  paramastoid  and  mastoid  tuberosities  are  narrowed  and  extend  ob 
liquely  downwards  and  forwards.  The  lower  part  of  the  exoccipital 
suture  runs  along  a  ridge,  and  there  is  a  tuberosity  in  front  of  the  mas- 
toid foramen.  An  irregular  A-shaped  crest  extends  upwards  with  the 
apex  at  the  inferior  temporal  crest,  and  its  anterior  limb  forming  part  of 
the  posterior  boundary  of  the  meatus  auditorium.  The  inferior  temporal 
crest  is  directed  outwards  below,  but  forwards  above. 

The  narrowness  of  the  cranium  is  readily  seen  on  comparing  the 
postglenoid  processes.  These  are  not  deep,  but  have  considerable  trans- 
verse extent,  and  are  separated  by  a  space  only  a  little  greater  than  the 
transverse  diameter  of  each.  The  zygomatic  arches  are  compressed  pos- 
teriorly with  crest-like  superior  ridge,  but  rounded  above  anteriorly. 
There  is  not  the  least  trace  of  posterior  boundary  of  the  orbit.  The 
squamosal  process  overlaps  the  malar  bone  extensively,  terminating  in  a 
point,  the  latter  ending  obtusely.  The  malar  is  supported  in  front  by  a 
maxillary  process,  which  is  united  with  it  by  a  zigzag  suture  on  the  outer 
face  and  a  squamosal  one  within  and  below.  The  foramen  infraorbitale 
exterius  is  large,  and  issues  a  short  distance  in  front  of  the  orbit,  not  so 
near  it  as  in  the  elephants.  From  this  point  to  the  ridge  enclosing  the 
canine  alveolus  the  side  of  the  maxillary  bone  is  deeply  concave,  and  the 
palatal  surface  correspondingly  contracted.  The  bone  is  continued  up- 
wards and  outwards  as  the  external  part  and  apex  of  the  middle  horn- 
cores.  Anteriorly  it  is  bounded  by  the  premaxillary  to  a  point  as  far 
anterior  to  the  base  of  the  horn  as  the  width  of  the  latter;  behind  that 
point  it  is  in  contact  with  the  nasals.  The  premaxillary  is  prolonged 
upwards  and  backwards  into  a  narrow  tongue.  Its  inferior  portion  is 
convex  above  on  each  side,  concave  below,  with  projecting  alveolar  bor- 
ders, which  are  flat  and  slightly  concave  fore  and  aft.  The  extremity  of 
each  is  rugose  below,  supports  a  prominent  tubercle  medially  and  a 
smaller  one  at  the  superior  angle. 

The  exterior  nares  are  not  separated  by  osseous  septum.  Their  lateral 
border  is  marked  on  the  inferior  surface  of  the  nasal  and  premaxillary 
roof,  by  a  curved  ridge  or  crest,  which  converge  forwards  and  bound  the 
interior  concavity  of  the  roof.  They  gave  support  to  muscular  or  liga- 
mentous  attachments.  The  posterior  angle  of  the  nares  is  abruptly  ex- 
cavated with  thickened  walls.  The  palate  is  remarkably  narrow,  and 
is  most  deeply  excavated  between  the  alveolae  of  the  tusks,  or  at  the 
maxillo-premaxillary  suture.  From  near  this  point  to  the  palatine  suture 
a  low  but  sharp  crest  extends  along  the  middle  line.  The  width  of  the 
palate  at  the  diastema  is  one  ninth  of  its  length.  The  diastema  is  more 
than  half  the  length  of  the  molar  series.  The  pterygoid  process  of  the 
palate  has  two  convergent  grooves  on  its  inferior  surface.  ^ 

The  teeth  are  remarkable  for  the  extent  of  the  exposure  of  their  slender 
roots,  as  well  as  their  very  small  size  a's  compared  with  the  size  of  the 
animal.  The  tusk  is  slightly  turned  outwards  at  the  tip  and  the  inner 
face  is  worn  by  attrition  with  some  opposing  tooth  for  one-third  its  length 


11 

on  the  posterior  third.  The  superior  margin  of  the  enamel  on  this  side 
is  chevron-shaped,  the  apex  being  only  one-third  the  length  from  the 
extremity.  It  extends  further  upwards  in  front  and  on  the  outer  side,  but 
is  worn  in  an  oval  patch  at  the  apex  of  the  chevron  of  this  side  by  contact 
with  the  inferior  teeth,  as  above  described.  The  enamel  is  smooth 
behind,  rugose  in  front.  The  apex  contracts  regularly  to  a  flattened 
obtuse  point.  The  fang  is  hollow  for  about  half  its  length.  The 
enamel  of  the  molars  is  nearly  smooth.  Each  one  has  a  strong  cingu- 
lum  fore  and  aft,  which  is  discontinued  on  the  inner  and  outer  faces  ex- 
cept in  P.  M.  1,  and  M.  2.  In  the  former,  it  is  continued  on  the  outer 
side  at  the  base  of  the  concavity  of  the  exterior  face;  on  the  latter,  it  is 
continued  round  the  inner  side.  The  grinding  surface  of  the  P.  M.  1, 
is  tripodal,  and  probably  composed  of  a  worn  crescent  and  inner  tubercle. 
The  others  are  transverse  arrow-shaped;  the  P.  M.  4  is  much  more  worn 
than  the  others.  M.  2  is  larger  than  M.  1.  Its  oblique  crests  have  evi- 
dently been  worn  from  before.  All  the  molars  have  three  roots,  but  the 
posterior  pair  are  united  for  part  of  their  length  in  all. 

The  corner  does  not  unite  with  the  superior  crest  of  the  palatine 
bones.  The  sphenoid  flattens  out  behind  the  post-nareal  trough  and  is 
coosified  with  the  basioccipital.  The  latter  is  marked  by  two  oval  sur- 
faces at  the  place  of  suture,  with  a  slight  prominence  between.  No 
lower  jaw  was  found  with  this  specimen,  but  from  the  contraction  of 
the  parts  opposed  to  it,  it  was  evidently  very  small. 

Cranial  Measurements. 

M. 
Length  from  end  nasals  to  end  occipital  condyle  (3 

feet  1.5  inches) 0.930 

Width  just  behind  end  nasal  shovels 192 

"      in  front  of  horns .132 

"      at  base  of  horns  in  front 205 

"     behind  horns  at  apex  of  frontal  suture 185 

"      above  posterior  edge  meatus  auditorium 310 

"     between  apices  horn-cores 370 

"     basis  supraoccipital  horn-core 100 

"     including  zygomatic  arches  (greatest) 320 

Length  of  nasal  bones  to  ridge  between  horn-cores. . .     .410 

"        "       "        "       "  frontal  suture 540 

"      of  zygomatic  fossa  above 230 

"     from  angle  iiares  to  end  shovel 205 

"  "      "     "  premaxillary 155 

"     from  end  premaxillary  to  basis  of  camine 120 

"       "  "  "      "        P.M.I 276 

"      of  molar  series 185 

"      of  palate 450 

"      of  pterygo-palatine  crest 200 

"      of  sphenoid  axis 185 

"      "  basioccipital  (with  condyles) 128 


12 

M. 

Width  between  tips  premaxillaries 070 

"     at  canine  alveoli 185 

"     between  canine  alveoli 080 

"      at  diastema 050 

"      between  last  molars '070 

"      pterygo-palatine  crests 065 

"      of  postglenoid  process 095 

"      between  postglenoid  processes 095 

"     basioccipital  at  front 073 

"  "  "  condyles 200 

"      of  space  for  lymphanic  chamber 034 

Length  tusk  on  curve  (12.7  inches) 320 

Diameter  at  middle  (antero-posterior) 050 

"         "  base  "  "        063 

"         "  middle  (transverse) 030 

11        "  crown  P.  M.  1  transverse 022 

"          "  antero-posterior 024 

"  "        M.  1     "  "        035 

"  "  "    transverse 034 

M.  2        "        043 

11     antero-posterior 045 

Elevation  of  shovel  above  base  of  apex  of  nasal .060 

The  measurements  may  require  some  correction  in  respect  to  the 
supraorbital  width,  where  the  cranial  walls  have  suffered  from  compres- 
sion. The  frontal  of  one  side  has  been  pushed  so  as  to  overlap  that  of 
the  other  by  about  an  inch. 

The  scapula  is  of  a  sub-triangular  form,  the  front  being  vertical,  the 
apex  directed  backwards  and  an  angle  upwards.  The  posterior  expansion 
is  considerable,  as  in  the  elephants,  while  the  superior  angle  is  acumin- 
ate and  much  produced  and  massive.  The  spine  is  much  elevated, 
bounding  a  deep  supraspinous  fossa.  It  is  truncate  in  front  descending 
to  near  the  border  of  the  glenoid  cavity.  Its  extremity  is  dilated  in 
alate  fashion,  equally  fore  and  aft,  and  not  posteriorly  only  as  in  the 
elephants.  The  glenoid  cavity  is  flattened  so  as  to  be  longitudinal,  and 
the  coracoid  is  a  rudi mental  tuberosity. 

Measurements  of  Scapula. 

JM-. 

Total  length  (25.25  inches) 0.640 

"     width 480 

Length  apex  from  spine 140 

Elevation  of  spine  proximally 125 

Length  of  glenoid  cavity 185 

Width    "          "  "       110 

The  interior  side  of  the  scapula  is  strongly  convex  by  the  development 


13 

of  two  longitudinal  ribs,  one  corresponding  to  each  fossa,  but  concave  in 
longitudinal  section. 

The  proximal  end  of  the  radius  exhibits  two  facets  oblique  to  each 
other,  the  larger  concave  and  transverse,  the  other  oblique  downwards. 
Transverse  width  M.  0.130  ;  vertical  .070.  The  extremity  of  a  humerus 
not  found  with  this  individual,  to  which  the  radius  applies  pretty  well, 
has  a  very  oblique  trochlear  face,  and  measures  seven  inches  across  the 
condyles.  It,  however,  belongs  to  a  smaller  species. 

The  femur  is  entire.  Like  that  of  other  species  of  the  group  it  is 
much  expanded  proximally  and  deep  distally,  with  the  shaft  contracted 
and  somewhat  flattened  in  the  plane  of  the  great  trochanter.  The  latter 
is  in  one  plane,  with  its  external  margin  turned  a  little  backwards.  The 
head  is  part  of  a  globe,  and  is  a  little  more  elevated  than  the  trochanter, 
and  separated  from  its  apex  by  a  shallow  concavity.  There  is  no  little 
trochanter.  The  trochlear  face  is  not  elevated  nor  wide,  and  with  lateral 
borders  subequally  developed.  The  aiitero-posterior  axis  of  the  con- 
dyles is  somewhat  oblique  to  a  line  at  right  angles  to  the  proximal  end. 
On  this  account  the  interior  coaidyle  is  the  longer ;  its  articular  face  is 
continuous  with  the  trochlear,  with  a  marginal  notch  ;  the  outer  condyle 
is  continuous,  with  continuous  outer  margin.  Strong  ridges  revolve 
from  above  the  condyles  to  the  posterior  face  of  the  shaft,  the  inner  near 
the  condyle.  The  outer  runs  parallel  to  the  main  axis  as  a  low  external 
ala,  and  backwards  three  inches  above  the  condyle.  The  face  between 
them  is  concave. 

Measurements  of  Femur. 

M. 

Total  length,  (31.75  in.) ' 0.747 

Total  proximal  width 255 

Diameter  of  ball 136 

Transverse  diameter  at  middle  of  shaft 096 

Antero-posterior  "  "  "    074 

"         condyles  posteriorly 150 

Transverse  "  "  "  160 

"  "  "          distally 145 

The  pelvis  has  a  large  transverse  expansion.  The  iliac  plates  are  ovoid 
in  outline,  with  the  apex  outwards  and  downwards.  The  margins  are 
rather  thin  excepting  the  internal  above  the  acetabulum.  These  are 
massive,  and  with  a  longitudinal  excavation.  They  terminate  in  a  deep 
oblique  excavation  for  the  diapophyses  of  the  sacrum.  The  external 
margin  rises  compressed  from  just  above  the  acetabulum.  The  latter  is 
large  for  the  size  of  the  ilia,  and  its  margins  rise  to  a  slight  elevation  be- 
neath the  exterior  margins  of  the  latter.  The  incisura  acetabuli  is  ob- 
clavate,  and  nearly  symmetrical.  The  os  ischium  is  compressed  and  deeper 
than  the  pubis.  It  possesses  a  tuberosity  on  the  posterior  inferior  mar- 
gin. The  obturator  foramen  is  small  and  is  a  vertical  oval.  The  pubis  is 
rather  slender  and  short.  '  Its  section  at  base  is  subtriangular;  beyond, 


14 

it  becomes  more  compressed,  and  is  spirally  twisted  on  itself  through 
part  of  a  circle.  Its  anterior  margin  near  the  symphysis  is  strongly 
rugose  for  the  origin  of  the  pectineus  muscle;  the  rugosity  extends  into  a 
band  on  the  outside  of  its  proximal  portion. 

Measurements  of  Pelvis. 

M. 

Long  diamater  of  ilium 0.605 

Transverse  do.  at  acetabulum 430 

Length  inferior  free  margin  do 250 

Long  diameter  acetabulum 150 

Shorter       "  "          130 

"  "       obturator  foramen 070 

Width  ischium  at  tuberosity 140 

Length       "       to         "  110 

Diameter  pubis  at  obturator  foramen 062 

Expanse  of  ilia  laid  on  a  flat  surface  and  with  sacrum 

fn  place  (4.2  ft.) 1.280 

The  general  character  of  the  pelvis  is  more  like  that  of  the  Elephant 
than  that  of  any  Perissodactyle.  It  agrees  with  the  former  and  differs 
from  that  of  the  Ehinocerus  in  the  shortness  of  the  pedestals  of  the  ilia 
or  rather  in  the  sessile  position  of  the  latter  on  the  acetabula;  also  in  the 
absence  of  production  of  the  iliac  crests  in  advance  of  and  above  the 
sacrum.  It  is  also  elephantine  in  the  shortness  of  the  inferior  elements 
of  the  pelvis. 

Of  vertebra,  there  are  preserved  a  dorsal,  two  lumbar,  and  some  sacral. 
The  first  is  very  short  and  transverse.  It  is  so  injured  that  I  can  only 
give  measurements.  The  base  of  the  transverse  neurapophysis  is  a  flat 
oval;  both  capitular  articular  surfaces  are  deep.  The  anterior  lumbar 
is  longer,  but  still  short;  its  articular  faces  are  slightly  concave.  The 
neural  arch  is  wide,  and  supports  the  diapophysis.  The  sides  of  the 
centrum  are  concave  and  pierced  by  foramina,  and  there  is  p,  strong 
rugose  hypapophysis.  The  section  at  the  middle  is  subtriangular.  I 
have  three  sacral  vertebra  which  are  separated  by  very  distinct  sutures. 
They  diminish  very  rapidly  in  size,  and  the  centra  become  flattened  trans- 
verse. It  is  doubtful  whether  there  was  a  fourth  vertebra,  and  the  tail 
must  have  been  short  and  slender.  The  articular  face  of  the  first  is 
a  transverse  rather  broad  ellipse  and  twice  the  diameter  of  the  third 
distally.  The  diapophysis  of  the  second  is  much  the  stoutest.  It  unites 
with  the  subvertical  plate-like  diapophysis  of  the  first  as  well  as  with 
that  of  the  third.  It  is  concave  above,  and  terminates  distally  in  a  mas- 
sive L-shaped  surface  of  articulation  with  the  ilium.  The  foramina  en- 
closed by  the  diapophyses  are  quite  large.  The  inferior  face  of  the  first 
sacral  centrum  is  slightly  concave  with  a  hypapophysial  tuberosity  in 
front;  it  is  strongly  concave  in  the  second. 


15 

Measurements  of  Vertebra. 

M. 

Antero-posterior  diameter  of  dorsal 0.044 

Diameter  at  bottom  neural  arch  do 040 

Length  base  of  neurapophysis 041 

Diameter  centrum  lumbar  (vertical) 090 

"  "  "        (transverse) 110 

"  "  "        (antero-posterior) 080 

Length  three  sacral  vertebrae 226 

Transverse  extent  of  sacrum  (15  in.) 380 

Diameterfirst  vertebra  at  free  end  (transverse)  (4.6  in.)     .122 

"          "          "  "         Vertical) 093 

<•       last         "  "  "        021 

"          "          "  "         (transverse) 065 

Total  expanse  of  heads  of  rib 106 

Diameter  capitular  face  (vertical) 048 

"        tubercular  "        030 

Width  rib  just  below  head .050 

Restoration.  We  may  ascribe  to  the  Loxolophodon  cornutus,  form  and 
proportions  of  body  similar  to  those  of  the  elephant.  The  limbs,  however, 
were  somewhat  shorter,  as  the  femur  is  stouter  for  its  length  than  in  the 
E.  indicus.  It  was  intermediate  in  this  respect  between  the  latter  species 
and  the  species  of  Ehinocerus.  The  tail  was  quite  small.  The  neck  was 
a  little  longer  than  in  the  elephants,  but  much  less  than  in  the  rhinoce- 
roses; the  occipital  crest  gave  attachments  to  the  ligamentum  mucJtce  and 
muscles  of  the  neck,  which  must  needs  have  been  powerful  to  support 
the  long  muzzle  with  its  osseous  prominences,  and  to  handle  with  effect 
the  terrible  laniary  tusks.  The  head  must  have  been  supported  some- 
what obliquely  downwards,  presenting  the  horns  somewhat  forwards  as 
well  as  upwards.  The  third  or  posterior  pair  of  horns  towered  above  the 
middle  ones,  extending  vertically  with  a  divergence,  when  the  head 
was  at  rest.  The  posterior  and  middle  pair  of  horns  were  no  doubt 
covered  by  integument  in  some  shape,  but  whether  dermal  or  corneous 
is  uncertain.  Their  penetrating  foramina  are  smaller  than  in  the  Bovidce. 
The  cores  have  somewhat  the  form  of  those  of  the  Antilocapra  americana, 
whence  I  suspect  that  the  horns  had  an  inner  process,  or  were  palmate 
as  in  the  prong-horn  at  present  inhabiting  the  same  region.  The  nasal 
shovels  may  have  supported  a  pair  of  flat  divergent  dermal  horns,  «but 
this  is  uncertain;  they  are  not  very  rugose. 

The  elevation  of  the  animal  at  the  rump  was  about  six  feet,  distributed 
as  follows: 

Inches. 

Foot 4.50 

Tibia '. . .  20.50 

Femur : 31.75 

Pelvis 16. 

72.75 


16 

The  anterior  limb  was  stouter  than  the  posterior,  judging  from  the 
proportions  in  Eobasileus  pressicornis,  and  were  no  doubt  more  elevated, 
if  of  the  Proboscidian  character.  This  would  give  us  the  hypothetical 

elevation  at  the  withers  : 

Inches. 

Leg 61.00 

Scapula  (actual) 21.00 

Neural  spines  (extremities) 7.00 

Or  seven  feet,  five  inches 89.00 

These  measurements  are  made  from  the  plantar  and  palmar  surfaces, 
allowance  being  made  for  the  pads. 

The  neck,  estimating  from  tne  dorsal  vertebrae  and  from  the  cervicals 
of  other  species  preserved,  could  not  have  exceeded  one  foot  in  length,  and 
may  hava  been  less.  This  added  to  the  length  of  the  cranium,  gives  a 
total  of  about  four  feet.  The  obliquity  of  the  antero-posterior  axis  of 
the  cervical  vertebrae,  indicates  that  the  head  was  posteriorly  elevated 
above  the  axis  of  the  dorsal  vertebrae.  Thus  it  is  entirely  clear,  that  the 
muzzle  of  this  animal  could  not  have  reached  the  ground  by  several  feet, 
and  that,  as  occurs  in  the  similar  cases  of  the  Tapirs  and  Elephants  tkere 
was  a  proboscis  to  supply  that  necessity.  The  indications  derived  from 
the  bones  of  the  muzzle  confirm  this  conclusion,  as  has  been  already 
pointed  out.  There  could  have  been  no  interference  from  the  horns  near 
the  ends  of  the  nasal  bones,  for  the  bases  of  these  project  beyond  the 
origin  of  a  proboscis,  and  were  directed  outwards  while  the  latter  hung 
downwards. 

This  species  was  probably  quite  as  large  as  the  Indian  Elephant,  for 
the  individual  described  is  not  adult,  as  indicated  by  the  freedom  of  the 
epiphyses  of  the  lumbar  vertebrae,  and  fragments  of  others  in  my  posses- 
sion indicate  considerably  larger  size. 

Habits.  The  very  weak  dentition  indicates  soft  food,  no  doubt  of  a 
vegetable  character,  of  what  particular  kind  it  is  not  easy  to  divine.  The 
long  canines  were  no  doubt  for  defense  chiefly,  and  may  have  been  use- 
ful in  pulling  and  cutting  vines  and  branches  of  'the  forest.  The  horns 
furnished  formidable  weapons  of  defense .  That  the  anterior  nasal  pair 
were  not  used  for  rooting  in  the  earth  is  evident  from  the  elevation  of  the 
head,  which  would  render  this  impossible. 

This  huge  animal  must  have  been  of  defective  vision,  *for  the  orbits 
have  no  distinctive  outline,  and  the  eyes  were  so  overhung  by  the  horns 
and  cranial  walls  as  to  have  been  able  to  see  but  little  upwards.  The 
muzzle  and  cranial  crests  have  obstructed  the  view  both  forwards  and 
backwards,  so  that  this  beast  probably  resembled  the  Rhinoceros  in  the 
ease  with  which  it  might  have  been  avoided  when  in  pursuit. 

Locality.  The  remains  of  the  Loxolophodon  cornutus  were  found  by  the 
writer  in  August,  1872,  in  a  ravine  of  the  bad  lands  of  Wyoming.  The 
greater  part  of  the  cranium  and  the  femur  were  excavated  from  the  base 
of  a  cliff  of  perhaps  250  feet  in  height,  on  the  side  of  a  ravine  elevated 


17 

about  1000  feet,  in  the  Mammoth  Buttes,  on  South  Bitter  Creek.  As 
the  basin  of  Bitter  Creek  is  7,500  feet  above  the  sea,  the  fossil  was  taken 
from  an  elevation  of  8,500  feet.  The  horizon  is  the  Bridger  Group  of 
the  Eocene  of  Hayden. 

EOBASILEUS.     Cope. 

Proceedings  of  the  American  Philosophical  Society,  1872,  p.  485  (Au- 
gust 20th). 

As  pointed  out  above,  this  genus  resembles  Loxolophodon  in  the  very 
short  cervical  vertebrae,  but  agrees  with  Uintatherium  in  the  rudimental 
condition  of  the  nasal  horn-cores,  which  are  mere  tubercles.  The  posterior 
or  third  pair  of  horn-cores  are  also  very  different,  and  probably  stand  on 
the  largely  developed  lateral  crests  of  the  superior  surface  of  the  cranium, 
as  in  Uintatherium.  They  are  apparently  preserved  in  E.  furcatum 
(which  is  not  the  type  of  the  genus),  and  are  compressed  from  base  to 
summit ;  in  Loxolophodon  the  base  is  nearly  cylindric. 

The  characters  of  this  genus  had  not  been  indicated  'in  any  of  the  de- 
scriptions published  by  palaeontologists  prior  to  its  establishment  as  above 
cited.  It  is  possible  that  Tinoceras  grandis  of  Marsh  may  be  synony- 
mous with  one  of  the  species  here  referred  to  it,  but  this  point  cannot  be 
determined  from  the  descriptions  of  that  author. 

The  cervical  vertebra  in  E.  pressicornis  are  very  short.  The  limbs  are 
much  as  in  Loxolophodon,  as  are  the  scapula  and  pelvis.  The  symphysi& 
pubis  of  E.  pressicornis,  or  an  ally,  is  short,  and  was  separated  from  the 
ischiadic  symphysis,  but  whether  this  belongs  to  the  genus  is  not  entirely 
certain. 

The  namcular  bone,  of  perhaps  the  same  species  as  the  above,  displays, 
as  in  living  proboscidians,  four  inferior  facets,  thus  proving  the  existence 
of  five  toes  to  the  hind  foot.  The  external  facet  is  deeply  concave,  and 
contains  a  pit.  It  is  oblique,  and  unites  with  the  superior  face  by  an 
acute  angle.  It  supported  the  small  inner  toe  by  its  metatarsus  directly. 
The  other  three  are  more  nearly  on  one  plane,  and  are  deeper  than  wide. 
The  navicular  is  in  form  a  little  less  than  a  quarter  of  a  circle,  and  the 
external  (anterior)  depth  is  one  half  its  transverse  length.  Its  superior 
surface  is  slightly  convex. 

EOBASILEUS  PRESSICOKNIS.    Cope. 

Loxolophodan  pressicornis,  Cope.  Proceed.  Amer.  Philos.  Soc.,  1872, 
p.  580  (published  August  19th).  Loc.  cit.,  p.  488  (August,  22).  Eobasil- 
eus  cornutus,  Cope,  1.  c.,  p.  485  (Aug.  20th),  not  Loxolophodon  cornutus, 
Cope,  1.  c.,  Aug.  19. 

Represented  by  numerous  portions  of  the  cranium,  with  fragments  of 
limbs  of  one  individual ;  of  almost  all  portions  of  the  skeleton  except  the 
cranium,  of  a  second.  A  humerus  with  astragalus  of  a  third  are  of  un- 
certain reference,  while  a  single  humerus  of  another  species  may  belong 
here.  Fragments  of  several  other  individuals  of  appropriate  size  may 
pertain  to  it. 


18 

The  cranium  is  represented  by  nasal,  maxillary,  malar,  occipital  bones, 
etc.  The  first  named  has  a  half  conic  apex,  and  an  oblique  compressed 
tuberosity,  which  forms  the  lateral  border  behind  it,  and  is  directed  ob- 
liquely upwards.  The  apex  of  each  nasal  is  vertically  compressed  acute, 
and  is  deeply  pitted  and  rugose  for  muscular  or  ligamentous  attachments. 
The  inferior  lateral  marginal  ridge  is  contracted,  and  encloses  a  concave 
median  space.  The  tuberosity  sinks  to  the  level  of  the  median  suture. 
The  posterior  part  of  the  nasal  rises  to  the  apex  of  the  middle  horn-core, 
forming  its  inner  face.  The  postero-superior  angle  of  the  premaxillary 
reaches  to  near  the  base  of  the  horn,  and  is  not  drawn  out  to  a  narrow 
apex  as  in  L.  cornutus.  The  horn  is  compressed  antero-posteriorly  at 
the  base;  at  the  apex  obliquely  inwards  and  forwards.  The  outer  face  is 
concave  on  the  lower  half,  the  inner  convex.  The  posterior  face  is  con- 
cave and  the  anterior  convex  when  viewed  from  the  side. 

Measurements  of  Nasal  Bone. 

M. 

Width  of  both  at  tuberosity 0.124 

11        base  of  distal  cone 060 

Depth  of  suture  at  front  of  tuberosity 030 

Length  of  suture  from  premaxillary  to  horn-core 035 

"  horn-core  (in  front)  (6  in.) 150 

Diameter  (externally) 080 

11        of  apex 048 

TJie  occipital  region  is  furnished  with  an  enormous  transverse  crest 
which  extends  upwards  and  backwards.  Its  margin  is  gently  convex, 
and  its  supero-anterior  face  concave.  The  posterior  is  narrowed  by  the  in- 
ferior crest-Uke  margins  of  the  temporal  fossa  which  extend  from  the  squa- 
mosal  part  of  the  zygoma  and  gradually  contract,  terminating  abruptly 
in  a  low  knob  where  it  joins  the  transverse  crest.  The  posterior  face 
between  the  former  is  divided  into  two  planes  by  a  low  vertical  ridge, 
which  terminates  some  distance  below  the  summit.  The-  transverse  crest 
is  continued  in  a  curve  forwards  on  each  side  as  the  superior  margin  of 
the  temporal  fossa.  The  specimen  does  not  indicate  whether  these  sup- 
ported horns,  but  they  are  very  stout. 

Measurements  of  Occiput. 

*  M. 

Elevation  from,  foramen  magnum 0.180 

Width  between  inferior  temporal  crests 250 

"       of  condyles  with  foramen 180 

Elevation  above  internal  sinuses  at  angles 180 

The  mastoid  tuberosity  is  short  and  stout ;  the  mastoid  foramen  is  large 
and  not  piercing  a  crest.  The  ex-occipital  suture  is  obliterated.  The  A- 
shaped  crest  behind  the  meatus  in  Loxolophodon  cornutus  is  little  marked 
here.  The  surface  of  the  bone  has  various  muscular  impressions.  The 
basi-occipital  exhibits  a  low  median  crest  dividing  lateral  concavities  ; 


19 

transverse  width  at  condyles  .077  M.  The  fragments  of  teeth  are  too 
uncharacteristic  for  specific  description.  Numerous  cranial  fragments 
accompany  the  above,  but  have  not  yet  been  properly  placed. 

The  atlas  is  broken  ;  its  cotyloid  cavities  are  rather  shallow,  and  the 
diapophyses  small.  Its  antero-posterior  diameter  below  at  the  middle 
line  is  .070  ;  at  base  of  diapophysis  ".070.  The  condyles  of  the  femur 
present  the  characters  of  the  group.  There  is  a  deep  vertical  groove  on 
the  inner  side  just  above  the  condyle.  The  latter  approach  each  other 
closely  on  each  side  of  the  intercondylar  fossa  and  are  flattened  on  the 
superior  posterior  margins.  Width  across  extremities  M.  .150. 

At  a  distance  of  one  or  two  hundred  feet  from  the  above  specimen  I 
found  portions  of  the  skeleton  of  a  smaller  animal,  probably  a  different 
but  allied  species.  It  is  represented  by  portions  of  ribs  and  limbs,  of  which 
the  ulna  is  described  under  Uintatherium.  Two  or  three  hundred  yards 
from  the  typical  specimen,  I  obtained  remains  of  almost  all  parts  of  the 
skeleton  of  what  is  probably  the  present  species.  The  femur  is  identical 
in  character.  The  specimen  embraces  cervical  dorsal  and  lumbar  verte- 
brae, ulna,  both  femora  and  tibiae,  astralagus,  navicular,  etc.,  and  large 
parts  of  the  scapulae  and  pelvis. 

The  scapula  in  its  proximal  portions,  differs  little  from  that  of  Loxo- 
lophodon  cornutus  besides  in  inferior  size.  The  coracoid  is  a  compressed 
tubercle  enclosing  a  groove  with  the  glenoid  cavity. 

M. 

Diameter  glenoid  cavity  (longitudinal) 0.168 

"  "  "       (transverse) 098 

The  os  pubis  displays  a  strong  pectineal  rugosity  commencing  near  the 
acetabulum. 

M. 

Long  Diameter  of  acetabulum 0. 143 

Length  ischio  pubic  suture 108 

Diameter  pubis  near  acetabulum 052 

The  femur  is  nearly  as  long  as  that  of  Loxolophodon  cornutus,  but  is 
more  slender,  and  has  a  relatively  smaller  head.  It  is  flattened  fore  and 
aft,  and  the  great  trochanter  is  much  expanded  and  with  a  shallow  con- 
cavity on  the  posterior  face.  There  is  a  marked  concavity  on  the  posterior 
face  of  the  shaft  above  the  condyles.  There  is  a  rudiment  of  the  little  tro- 
chanter. The  tibia  is  scarcely  three-fourths  the  length  of  the  femur,  and 
has  a  rather  contracted  shaft,  which  is  in  section  rounded  triangular,  one 
angle  presenting  forwards.  There  is  no  spine  except  a  rudiment  in  the 
swollen  upper  portion  of  the  anterior  ridge.  The  articular  surfaces  are 
together  rather  narrowly  transverse.  They  are  separated  by  a  keel  which 
is  undivided  posteriorly  ;  anteriorly  the  contiguous  margins  of  the  cotyli 
separate.  The  long  axis  of  the  inner  of  these  is  directed  antero-posteri- 
orly  outwards  in  front ;  of  the  other  similar  but  much  more  transverse. 
It  overhangs  the  shaft  outwards  and  backwards  and  supports  beneath, 
the  subround  down-looking  fibular  articular  surface.  The  distal  articu- 


20 

lar  surface  is  distinguished  from  allied  species  by  the  downward  promi- 
nence of  the  malleolar  process,  the  antero-posterior  width,  and  the  greater 
extent  of  the  fibular  articular  face.  The  face  is  slightly  concave  antero- 
posteriorly  and  openly  sigmoidal  transversely. 

Measurements  of  Leg. 

JM. 

Length  with  astragalus  in  place 1.200 

Femur,  length 750 

"        diameter  ball 118 

"        width  at  great  trochanter 220 

"  "      "  middle  shaft 091 

"        depth  "          "     060 

Tibia,  length .470 

u    width  proximal  surfaces  (transverse) 147 

"  "  "          (antero-posterior) 070 

"      transverse  diameter  shaft 061 

"      antero-posterior          "          065 

"  "      distal  articulation 092 

"      transverse  "          "  "  121 

Fibula,  length .% 430 

**        transverse  width  at  middle 032 

"        width  proximal  articular  face 042 

"  "     malleolar        "        "   (transverse) 052 

"  "  "  "        "   (longitudinal) 044 

A  section  of  the  fibula,  near  the  proximal  end,  is  sub-triangular  ;  a 
short  distance  below,  sub-circular;  on  the  distal  two-thirds  it  is  flat,  with 
the  thinner  edge  convex  inwards. 

The  astragalus  is  a  flat  bone,  with  its  entire  superior  face  occupied  by 
the  tibial  articular  surface.  This  is  as  broad  as  long,  and  very  little 
convex.  It  is  broader  in  front  than  behind  ;  the  outer  margin  is  concave, 
the  inner  slightly  convex.  The  posterior  margin  projects  most  on  the 
outer  side,  and  it  is  divided  by  a  pit-like  cavity,  which  sends  a  groove  to 
the  inner  margin.  The  outer  malleolar  surface  is  an  antero-posterior 
oval ;  the  inner,  a  concavity,  beyond  which  the  inferior  portion  of  the 
bone  projects.  The  inferior  face  is  divided  by  a  prominent  transverse 
angle,  between  sub-anterior  and  sub-posterior  faces.  The  latter  receives 
the  calcaneum  on  two  oval  surfaces,  which  are  joined  behind  by  a  narrow 
strip.  The  navicular  face  is  sub-rhomboid,  the  cuboid  one-third  as  large, 
and  triangular,  with  a  round  base  outwards.  The  margin  of  the  former 
scarcely  projects  beyond  the  superior  face. 

Measurements  of  Astragalus. 

M. 

Total  width 0.128 

"     length 107 

Width  tibial  face  in  front. .  .090 


21 

M. 

Length  tibial  face  externally 088 

"       internal  malleolar  face 045 

"       outer  calcaneal  do.  antero-pesteriorly 050 

Length  navicular  facet 095 

Width  do.  (antero-posterior) 060 

Length  cuboid  facet 065 

Width  do.  (antero-posterior) 035 

A  navicular  belonging  to  the  individual  mentioned  first  has  been  already 
described. 

Measurements  of  Navicular. 

M. 

Depth  in  front 048 

Width  (transverse) 097 

"       of  external  facet.. 035 

"        "   second 026 

"  third 047 

"        "   internal 023 

A  distal  end  of  a  humerus  was  found  with  two  astragali  about  a  hun- 
dred yards  from  the  last  individual.  The  articular  face  is  very  oblique 
to  the  transverse  axis,  but  is  about  equally  developed  on  opposite  sides  of 
the  shaft.  The  condyles  are  unequal,  have  parallel  axes,  and  are  separated 
by  but  a  shallow  concavity.  The  fossae  of  opposite  sides  are  not  very 
large  nor  deep. 

Measurements  of  Humerus. 

M. 

Transverse  diameter  distally 175 

Do.  of  inner  condyle 104 

"     outer        "       125 

Transverse  diameter  olecranon 110 

The  portion  of  ulna  just  measured  belongs  to  the  individual  of  which 
so  many  fragments  were  found,  or  No.  2. 

The  dorsal  vertebrae  of  the  same  are  somewhat  distorted  by  pressure  ; 
I  will  therefore  describe  a  cervical  of  natural  form.  The  centrum  is  very 
short,  and  the  articular  face  is  a  wide,  transverse  oval.  Both  are  slightly 
concave,  and  the  axis  being  slightly  oblique,  the  anterior  is  the  more 
elevated.  The  surface  of  the  latter  is  quite  rugose,  except  on  the  margins. 
The  cervical  canal  is  wide,  and  the  neur-  and  parapophyses  narrow.  In- 
ferior surface  regularly  convex. 

Measurements  of  Cervical  Vertebra. 

M. 

Length  centrum 044 

"       basis  neurapophysis 040 

"       anterior  articular  face 102 

Depth  "  "  086 

Width  neural  canal  at  base ...  .060 


22 

Restoration.  The  elevation  of  this  animal  was  not  much  less  than  that 
of  the  LoxolopJiodon  cornutus,  but  the  proportions  were  more  slender.  As 
in  all  the  species  of  Uintatherium  in  which  the  horns  are  known,  these 
appendages  stood  in  front  of  the  orbits,  and  nearer  the  nareal  opening 
than  in  the  type  of  the  former  genus.  The  muzzle,  too,  is  materially 
shorter  and  more  contracted,  and  the  true  apex  of  the  muzzle  was  not  over- 
hung by  the  great  cornices  seen  in  Loxolopliodon.  The  horn-sheaths  were 
probably  simple,  while  in  L.  cornutus  they  were  probably  palmate.  The 
occipital  and  parietal  crests  are  much  more  extended  in  this  species  than 
in  the  L.  cornutu%  so  that  in  life  the  snout  and  muzzle  had  not  such  a 
preponderance  of  proportion  as  in  that  species.  All  the  species  of  this 
genus  were  rather  more  rhinocarotic  in  the  proportions  of  the  head, 
although  the  horns  and  tusks  produced  a  very  different  physiognomy. 
The  extremities  of  the  nasal  bones,  though  not  excavated  as  in  that 
species,  are  strongly  pitted  and  exostosed,  and  this  taken  in  connection 
with  the  elevation  of  the  head  renders  it  probable  that  this  species  also 
possessed  a  proboscis. 

History.  This  species  was  originally  described  by  the  writer  in  a  short 
paper,  which  was  published  and  distributed  August  19th,  1872,  under  the 
generic  name  Loxolophodon.  I  shortly  afterwards  referred  it  to  the  new 
genus  Eobasileus,  under  the  name  cornutus,  under  the  impression  that  it 
was  the  same  as  the  Loxolophodon  cornutus;  but  finding  this  was  not  the 
case,  I  again  used  the  specific  name  here  adopted.  More  than  a  month 
later  Prof.  Marsh  (September  21st)  described  a  species  under  the  name 
of  Tinoceras  grandis,  which  agrees  with  this  one  so  far  as  relates  to  the 
length  of  horn-cores,  but  that  it  is  the  same  species  cannot  now  be 
positively  asserted.  I  originally  (August  20th,  1872)  alluded  to  the 
horn-cores  as  situated  on  the  frontal  bones  ;  Marsh  has  since  asserted 
them  to  be  composed  of  the  maxillaries.  I  have  discovered  on  the  first 
opportunity  of  making  a  detailed  examination,  that  the  inner  face  is 
composed  of  the  posterior  part  of  the  nasal  bones,  and  the  exterior  of 
the  maxillaries. 

EOBASILEUS   FUBCATUS.       Cope. 

Loxolophodon  bifurcatus,  Cope,  in  extra  copies  on  Proboscidians  of  the 
Eocene  of  Wyoming,  August  19th  1872.*  Loxolophodon  furcatus  in  the 
same,  Proceedings  American  Philosophical  Society,  1872,  p.  580,  Aug- 
20th.  L.  c.  488,  August  22d. 

This  species  was  originally  described  from  a  large  horn-core  whose 
extremital  part  resembles  strongly  the  nasal  shovel  of  Eobasileus  cor- 
nutus, on  which  account  I  referred  it  to  that  position  on  the  skull. 
Marsh  has  described  somewhat  similar  horn-cores  from  the  lateral  crests 
of  the  skull  behind  in  II.  mirabile,  whence  it  may  be  that  my  specimen  is 
referable  to  that  position,  although  it  differs  much  from  those  of  that 
species. 

*  See  Proceedings  American  Philosophical  Society,  1872,  p.  515,  where  this  name  is  recorded. 


23 

The  basis  is  very  narrow  and  lenticular  ;  a  short  distance  above  it  the 
outer  side  is  convex.  The  anterior  and  posterior  extensions  of  the  base 
differ  ;  the  one  is  thinner,  the  other  more  massive  and  with  a  shallow 
groove  above  its  commencement.  The  latter  may  be  posterior.  If  so, 
the  compressed  apex  of  the  horn-core  sends  down  a  rib  outwardly  to  the 
anteriorly  and  one  inwardly,  which  disappears  on  the  convex  base.  The 
general  form  is  spatulate  with  the  apex  expanded  obliquely  across  the  lat- 
eral crest,  and  regularly  rounded  in  superior  outline.  Its  anterior  face 
is  flat,  the  posterior  convex ;  its  surface  is  grooved  by  very  small  blood 
vessels. 

As  compared  with  the  posterior  horn-core  of  Loxolophodon  cornutus, 
there  is  every  difference.  That  is  continuous  with  one  margin  of  the 
crest ;  this,  erect  above  it ;  that  has  a  round  base,  this  a  lenticular  one. 
It  is  more  like  that  of  U.  mirabile,  which  I  only  know  from  Marsh's  figure, 
but  abundantly  distinct.  It  is  much  more  elongate,  especially  above  the 
posterior  ?  part  of  the  crest,  and  is  flattened,  and  without  the  triangular 
section  of  that  species. 

Measurements  of  Horn-core. 

M. 

The  total  length  above  crest  (5.5  inches) 0. 135 

"       "         "          "       base  (7^  inches) 180 

Width  across  apex  (in  front) * 095 

Thickness  across  apex  (in  front) 028 

"'      at  base 040 

It  is  not  certain  that  this  horn  may  not  belong  to  the  E.  pressicornis,  if 
it  be  a  posterior  core,  of  which,  however,  I  am  not  yet  entirely  sure.  In 
that  case  the  name  furcatus,  under  which  it  was  first  described,  becomes 
a  synonym  of  E.  pressicornis. 

UINTATHERIUM.    Leidy. 

Proceedings  Academy  Natural  Science's,  Philadelphia,  1872,  page  169 
(published  early  in  August).  Dinoceras,  Marsh,  Amer.  Journ.  Sci.  Arts, 
1872.  October,  1872  (published  September  27). 

This  genus  resembles  the  last  in  its  general  proportions,  but  differs  in 
its  more  elongate  cervical  vertebrae.  The  centra  of  these  are  flat  at  both 
extremities,  but  have  not  such  a  marked  elephantine  abbreviation  as 
seen  in  the  two  genera  above  described.  This  enabled  the  head  to 
approach  the  ground  more  nearly,  and  as  the  limbs  were  shorter  in  some 
of  the  species,  they  no  doubt  modified  the  length  of  the  proboscis,  if 
present. 

Several  names  have  been  applied  to  this  genus.     Professor  Leidy's 
name  here  employed,  bears  date  early  in  August,  but  of  the  precise  day 
I  am  not  informed.     Professor  Marsh,  in  the  Am.  Jour.  Sci.  and  Arts,  „ 
1872  (Sept.  21st),   applied  the  name    Tinoceras  toj  a  species  (T.  grandis] 
perhaps  of  this  genus,  and  gave   a  description  in  which  some  of  the 


24 

generic  characters  may  have  been  mentioned.  He  had  previously  applied 
it  without  description  to  the  Uintatherium  anceps,  Aug.  24th  (and  19th*, 
in  an  erratum,  where  Mastodon  anceps  is  altered  into  Tinoceras  anceps}. 
As  no  characters  whatever  were  assigned  to  it  on  either  of  these  occa- 
sions, it  had  no  value  in  zoological  nomenclature,  and  must  bear  date 
September  21st.  Under  date  of  September  27th,  Prof.  Marsh  proposed 
the  name  Dinoceras  (American  Journal  Science  Arts,  1872)  for  the  V. 
mirabile,  but  did  not  give  his  reasons  for  separating  it  from  his  former 
genus  (the  names  of  the  two  bear  an  objectionable  resemblance),  or 
those  published  by  Dr.  Leidy,  or  myself.  Until  such  reasons  be  adduced, 
I  retain  it  also  in  Uintatherium,  as  is  done  by  Dr.  Leidy. 

I  am  acquainted,  by  autopsy,  with  two  species  of  this  genus.  None  of 
them  are  so  large  as  the  Eobasileus  pressicornis  ;  U.  robustum,  Leidy, 
is  smaller,  and  the  U.  lacustre,  Marsh,  smaller  still.  U.  mirabile 
(Dinoceras,  Marsh)  is  about  the  size  of  the  U.  robustum,  and  nearly  allied 
to  it ;  but  it  may  be  distinct,  as  it  has  a  larger  mastoid  process.  Tinocera* 
grandis,  Marsh,  agrees  in  measurements  with  the  E.  pressicornis,  and  is 
perhaps  that  species  or  the  E.  furcatus.  The  Tinoceras  anceps,  Marsh, 
has  been  so  imperfectly  characterized  as  to  be  practically  unknown.  It 
is  one  of  the  smaller  species,  and  is  most  likely  to  be  identical  with  the 
IT.  robustum,  whose  name  it  antedates.  Until  these  points  be  cleared  up, 
I  retain  three  species,  as  follows  :  Uintatherium  robustum,  Leidy  ;  U. 
mirabile,  Marsh  ;  U.  lacustre,  Marsh.  For  convenience  I  compare  these 
species  with  those  of  Eobasileus. 

The  naso-maxillary  horn-cores  have  been  seen  in  E.  pressicornis  and  U. 
mirabile,  and  the  nasal  tubercles  in  the  same.  The  posterior  horn-cores 
are  known  in  the  U.  mirabile.  The  posterior  and  lateral  crests  of  the 
cranium  inclose  a  basin-shaped  concavity  above  in  all  these  species ;  it 
has  been  observed  in  all  but  E.  furcatus.  The  dentition  is  similar  to 
that  in  Loxolophodon,,  i.e.,  I.  0 ;  C.  1  ;  P.  M.  4  ;  M.  2.  The  first  premolar 
in  U.  lacustre  has  an  internal  cone  and  outer  concave  crest.  The 
worn  surfaces  of  the  other  teeth  in  that  species,  U.  robustum  and 
U.  mirabile,  are  narrow  ovate,  with  a  deep  exterior  emargination.  The 
true  molars  support  two  crests,  which  converge  inwards  and  unite  with 
a  small  tubercle  behind  the  apex  in  U.  lacustre  and  U.  robustum.  The 
tusk  is  long,  compressed  and  double-edged,  as  in  Loxolophodon. ,  The 
last  inferior  molar  in  U.  robustum  possesses  three  transverse  crests,  the 
posterior  two  parallel,  and  obliquely  directed  inwards  towards  the  axis 
of  the  anterior,  which  is  the  highest. 

In  a  specimen  of  one  of  the  smaller  species,  the  ulna  widens  consider- 
ably distally,  being  nearly  as  wide  as  the  olecranon.  The  latter  is  large, 
flattened  and  subtransverse,  and  presents  a  sharp  ridge  internally.  On 
the  inner  side  of  the  distal  part  of  the  articular  face  for  the  humerus  is  a 
tubercle,  from  which  a  short,  wide  groove  runs  out  on  the  inner  face  of 

*  These  papers  were  riot  recaived  by  me  till  early  iu  December,  1872. 


25 

the  bone,  the  head  of  the  radius  is  a  little  exterior  to  the  middle  line,  and 
the  shaft  crosses  the  ulna  in  an  open,  shallow  groove  to  the  inner  side. 

The  cuboid  is  flat,  and  displays  two  proximal  and  two  distal  articular 
facets  in  P .  fftrcatum.  The  astragalus  of  the  same  species  is  subbifurcate 
posteriorly,  and  has  internally  an  extensive,  oblique  malleolar  fossa.  The 
calcaneum  is  short  and  massive,  with  two  superior  and  one  small  anterior 
articular  facet. 

The  species  may  be  thus  distinguished  : 

1.  Large  species  (occipital  condyles  extending  over  about  M.  0.170.) 
Naso-maxillary  horns  long  ;   tibia  with  wide  articular 

faces E.  pressicornis. 

Horn-cores  flat,  elevated E.  furcatus. 

2.  Species  of  intermediate  size. 

A  prominent  mastoid  process,  molars  smaller V.  robustum. 

Mastoid  process  not  prominent;  maxillary  horn-cores  low, 
triangular;  posterior  horn-cores  short,  triangular  in  section       II.  mirabiU. 
8.  Smallest  species  (occipital  condyles  extending  over  about  M.  0  .95.) 
Molar  teeth  larger,  the  last  with  a  posterior  expansion. .        IT.  lacustre. 
Previous  to  describing  the  species  I  notice  a  part  of  the  skeleton  of  a 
large  mammal,  second  only  in  bulk  to  Loxolophodon  and  Eobasileus  above 
described. 

These,  which  were  not  found  in  association  with  a  cranium,  consist 
of  several  vertebrae,  some  carpal  bones,  the  entire  hind  limb  of  the  left 
side  except  the  toes  and  the  cuneiform  and  navicular  bones. 

The  odontoid  process  is  very  stout,  with  a  descending  trihedral  apex. 
Length  M.  .078,  diameter  at  base,  .048.  A  dorsal  vertebra  with  a  single 
(anterior)  capitular  articular  face,  is  quite  concave  in  front. 

M. 

Diameter  antero-posteriorly 057 

"        vertically 094 

A  cervical  vertebra  has  the  proportions  of  the  dorsal  as  to  its  centrum, 
thus  differing  materially  from  species  previously  described.  The  articu- 
lar surfaces  are  slightly  concave. 

jM. 

Length  (antero-posteriorly) 0.065 

Diameter  vertical 087 

' '        transverse 100 

The  femur  resembles  that  of  the  other  species  already  described,  but 
is  remarkable  for  the  relatively  small  size  of  the  head.  While  the  lengths 
of  the  bone  are  not  very  different,  and  the  expanse  of  the  great  trochaiiter 
about  the  same,  the  head  of  L.  cornutus  is  large,  the  present  one  is 
very  much  smaller,  and  that  of  E.  pressicornis  intermediate.  There  is  a 
rudimental  third  trockanter,  and  the  condyles  are  as  large  as,  and  similar 
to  those  of,  E.  pressicornis.  The  external  marginal  condylar  ridge  is 
quite  short.  The  shaft  is  broken  and  some  small  pieces  lost ;  it  is  now  26 
inches  long,  but  was  no  doubt  longer  when  complete. 


26 

Measurements  of  Femur. 

M. 

Expanse  of  great  trochanter 0.230 

Diameter  of  head *  .   -109 

"          "  shaft  at  middle 093 

"        above  condyles 152 

"        at  extremity  of  condyles 139 

11        (vertical)  of  inner  condyle 125 

The  tibia  is  perfectly  preserved.  It  is  short  and  stout  and  with  massive 
extremities.  The  outer  basal  part  of  the  spine  remains  and  is  prominent. 
The  cotyli  are  not  oblique  ;  the  inner  is  subround,  the  outer  transverse, 
widening  outwardly ;  their  long  axes  are  at  right  angles  to  each  other.  The 
crest  is  a  low  ridge  of  contact  of  the  cotyli.  The  superior  fibular  face  is 
a  transverse  oval ;  the  inferior  much  smaller  than  in  E.  pressicornis.  The 
shaft  is  contracted,  and  flattened  behind  and  on  the  inner  side.  The  dis- 
tal extremity  is  transverse,  less  truncated  for  the  fibula  than  in  E.  pressi- 
cornis, less  convex  behind,  and  with  a  less  prominent  external  malleolus- 
The  point  dividing  the  astragalus  behind  is  more  prominent. 

Measurements  of  Tibia. 

M. 

Total  length 0.398 

Diameter  head  .longitudinal 080 

"  "    transverse 138 

"        shaft  transverse 063 

"  "    antero-posterior 060 

"        distal  articulation    " 077 

"  "  "  transverse 113 

"  "    extremity,  fore  and  aft 093 

"  "  "  transverse , ,125 

These  measurements  show  that  this  bone  is  considerably  shorter  than 
in  E.  pressicornis,  though  of  equal  distal  diameters.  In  both  species  the 
measurements  considerably  exceed  those  given  by  Marsh  for  his  Titano- 
therium  (?)  anceps.  The  form  of  the  articular  extremities  differs  from 
both  in  being  more  narrowed  and  transverse. 

The  fibula  is  larger  proximally  and  smaller  distally  than  in  E.  pressi- 
cornis. Diameter  proximal  articular  face  .039  ;  of  the  distal  .045. 

The  astragalus  is  similar  in  size  and  form  to  that  of  E.  pressicornis,  but 
differs  in  two  points.  The  posterior  margin  is  deeply  incised  for  the  lig- 
amentous  insertion,  and  the  outer  lobe  is  clearly  cut  to  this  fossa,  on  the 
inner  side.  There  is  a  pit  for  a  ligament  on  the  convexity  of  the  inner 
part  of  the  middle  of  the  tibial  articular  face.  A  third  difference  is  seen 
on  the  inferior  face.  The  inner  calcaneal  facet  is  longer  and  narrower, 
and  is  margined  on  the  inner  side  by  a  large  fossa  parallel  to  its  axis, 
which  is  wanting  in  the  other  species.  The  calcaneum  is  short  and  wide ; 


27 

its  only  anterior  articulation  is  with  the  cuboid  and  is  small.     The  heel  is 
deeper  than  long  and  is  obliquely  truncate  downwards  and  inwards. 

Measurements  of  Calcaneum. 

M. 

Length r.  0.105 

Width •.   .092 

Depth  in  front 056 

Length  heel 047 

Depth      "     055 

Length  cuboid  facet 038 

The  cuboid  is  a  flat  sub-triangular  bone  with  two  unequal  articular 
faces  below. 

M. 

Length 064 

Width 076 

Depth 031 

Length  cuneiform  (antero-posterior) 040 

Depth  "          017 

A  humerus  of  a  third  specimen  may  or  may  not  belong  to  this  species. 
It  was  found  in  another  locality.  Its  condyles  are  much  less  oblique  than 
in  that  one  described  under  E.  pressicornis.  It  belonged  to  a  larger 
animal,  see 

Measurements  of  Humerus. 

M. 

Transverse  diameter  distally  (7.75  in.) 195 

"  "        inner  condyle 125     ' 

The  olecranar  fossa  is  shallower. 

Remarks. — The  remains  were  discovered  by  the  writer  in  the  Bridger 
Bad  Lands  on  South  Fork  of  Bitter  Creek,  Wyoming. 

UlNTATHERIUM   ROBTJSTUM.       Leidy. 

Proceedings  Academy  Natural  Sciences,  Philadelphia,  1872,  p.  169, 
August.  Uintamastix  atrox,  Leidy,  1.  c.  (?  ?)  Titanotherium  anceps,  Marsh, 
American  Journ.  Sci.  Arts,  1871,  p.  35. 

I  have  been  able  to  examine,  through  the  kindness  of  Prof.  Leidy,  the 
type  of  his  description,  and  find  it  to  belong  to  a  smaller  species  than  any 
of  those  above  described.  The  lateral  parietal  and  supra-occipital  crests 
are  well  developed,  and  the  latter  extends  obliquely  backwards.  Several 
peculiarities  are  to  be  observed  in  the  dentition.  Thus  there  is  great  in- 
equality in  the  height  of  the  transverse  crests  of  the  posterior  upper 
molar,  the  anterior,  or  the  arched  one,  rising  to  a  high  cusp  at  its  outer 
extremity.  A  small  tubercle  exists  on  the  side  of  the  inner  angle  of  the 
grinding  surface  in  the  penultimate  molar.  The  same  angle  is  much 
elevated  in  an  anterior  molar.  The  canine  is  wider  distally  than  in  Z. 


28 

cornutus,  and  less  recurved.  The  mastoid  process  is  quite  prominent. 
The  humerus  has  a  prominent  internal  condyloid  ridge  and  tuberosity, 
and  the  condyles  are  not  very  oblique.  The  inner  posterior  lobe  of  the 
tibial  face  of  the  astragalus  is  quite  well  denned  ;  there  is  no  median 
ligamentous  pit  on  the  trochlear  face. 

Measurements  (from  Leidy). 

Inches. 

Depth  lower  jaw  at  last  molar 3.25 

Length  humerus  about 21. 

Diameter  at  condyles 7.50 

Found  by  Dr.  J.  V.  Carter  and  Dr.  Leidy  near  Fort  Bridger,  Wyoming. 

Dr.  Leidy  has  suggested  that  this  species  and  the  Dinoceras  mirabilis 
of  Marsh  are  identical. 

UlNTATHERIUM  MIRABILE.      Marsh. 

Dinoceras  mirabilis,  Marsh,  Amer.  Journ.  Sci.  Arts,  1872,  October 
(published  Sept.  27).  Loc.  cit.  Jan.  28th,  1873. 

The  cranium  of  this  species  has  been  very  partially  described  as  above 
cited,  but  from  figures  in  the  last  named  paper,  largely  supply  the  de- 
ficiency. From  this  it  is  evident  that  it  differs  from  LoxolopJiodon  cornutus 
in  the  generic  characters  already  mentioned,  and,  further,  in  the  anterior 
position  of  the  naso-maxillary  horns,  the  perforation  of  the  lachrymal,  the 
anterior  development  of  the  malar,  the  oblique  occiput,  &c.  It  differs 
from,  the  E.  pressicornis,  besides  the  inferior  size,  in  the  shorter  nasal 
bones  and  greater  posterior  approach  of  the  pre-maxillary  bones  to  the 
base  of  the  horns  ;  in  the  much  shorter  horns  and  greatly  smaller  part 
taken  in  their  composition  by  the  nasals. 

These  differences  account  for  the  great  number  of  errors  committed  by 
Prof.  Marsh  in  his  allusions  to  other  species,  especially  LoxolopJiodon 
cornutus  described  by  me  (see  his  second  article  above  quoted) . 

Measurements.     (From  Marsh). 

M. 

Length  of  cranium  (28.5  inches) 722 

Width  over  orbits 202 

"     between  summits  naso-maxillary  cores 169 

"  "  "        nasal          "  038 

Height  naso-maxillary  cores  (3  inches) , 075 

Length  canine  (9.25  inches)  below  jaw 232 

Diameter  fore  and  aft  at  base 064 

"       transverse     "      "    025 

Length  of  molar  series 150 

Last  superior  do 036 


29 

UlNTATHERIUM    LACUSTRE.      Marsh. 

Dinoceras  lacustris,  Marsh,  1.  c.  October,  1872.  (Published  September 
27th,  1872.) 

I  have  several  of  the  teeth  and  the  occipital,  parietal  and  other  por- 
tions of  the  cranium  of  this  species.  It  is  distinguished  from  its  con- 
geners, apart  from  its  smaller  size,  by  the  large  size  of  teeth.  These  are 
nearly  as  large  as  those  of  Loxolophodon  cornutus,  and  considerably  larger 
than  those  of  U.  robustum  and  U.  mirabile.  The  occipital  condyles  are 
not  larger  than  those  of  the  Elk,  Cervus  canadensis.  The  mastoid  pro- 
tuberance is  prominent,  and  the  post-glenoid  process  more  produced 
downwards  and  with  less  fore  and  aft  diameter  than  in  the  other  three 
species.  The  inferior  temporal  ridge  is  strongly  marked,  and  the  pos- 
terior condyloid  foramen  is  large. 

The  posterior  molar  has  a  wide  floor  extending  from  the  posterior  or 
straight  transverse  crest  to  the  cingulum.  This  crest  is  low  and  has  a 
low  tubercle  near  its  apex  behind.  The  other  molars  have  strong  fore 
and  aft  cingula  but  none  at  ends.  The  worn  surfaces  are  first  V-shaped, 
later  arrow-shaped.  The  first  premolar  has  curved  outer  crest  and  inner 
conic  tubercle. 

Measurements. 

M. 

Diameter  of  occipital  foramen  and  condyles 092 

From  exterior  end  condyle  to  mastoid 058 

"          "          "         "       to  post-glenoid  process 080 

Transverse  diameter  last  upper  molar 045 

"  "        third  premolar 029 

Length  molar  series 163 

Found  by  the  writer  in  the  Bridger  formation  of  South  Bitter  Creek, 
Wyoming. 

MEGACERATOPS.    Leidy. 

Proceedings  Academy  Natural  Sciences,  1870,  p.  1.  Hayden's  Geo- 
logical Survey,  Wyoming,  1872,  352  ("Megacerops"). 

This  genus  is  only  known  from  the  extremity  of  the  nasal  bones  bear- 
ing the  horn-cores.  The  latter  are  intermediate  in  position  to  the  nasal 
and  naso-maxillary  horns  of  Eobasileus,  etc.,  and  may  represent  the 
median  pair,  in  which  case,  the  diagnosis  of  the  genus  should  be,  nasal 
horn-cores  wanting. 

The  genus  was  originally  regarded  by  Dr.  Leidy  as  allied  to  Sivatheriitm 
and  therefore  Ruminant ;  he  also  supposed  that  it  possessed  a  proboscis 
"as  in  the  tapir."  The  latter  proposition  has  much  in  its  favor,  especi- 
ally as  the  affinities  of  the  genus  are  evidently  with  the  Proboscidia. 

MEGACERATOPS   COLORADOENSIS.     Leidy. 
Megacerops  Coloradoensis.     Leidy,  i.  c. 
The  part  of  this  species  preserved,  indicates  an  animal  of  the  size  of 


30 

the  largest  Uintatheria.  The  nasal  bones  are  coossified,  and  the  hornT 
cores  are  sub-cylindric,  obtuse  and  about  two  inches  in  length.  They 
are  situated  above  a  point  a  little  behind  the  anterior  nares. 

PANTODONTA. 

As  already  pointed  out,  the  structure  of  the  limbs  and  feet  in  this 
suborder  is  as  in  the  order  generally,  and  the  scapula  has  the  same  form 
in  general.  There  is  also  a  resemblance  in  the  form  of  the  symphysis 
mandibuli,  which  though  furnished  with  teeth,  forms  a  long  solid  spout 
comparable  to  that  of  the^  Elephant.  The  astragalus  has  a  very  peculiar 
form,  being  even  more  exceptional  than  in  Uintatherium.  The  superior 
articular  surface  is  flat  or  concave  in  the  middle.  It  is  turned  inwards 
in  front  of  the  articular  face  fot  the  inner  malleolus,  terminating  in  a 
long  point.  The  cuboid  articular  face  is  quite  small  and  sublateral. 
The  fibular  facet  is  extensive,  and  the  internal  lateral  well  marked. 

On  the  other  hand  the  coracoid  process  is  produced  into  a  curved  hook, 
and  is  thus  more  largely  developed  than  in  other  Proboscidians  or  Peris- 
sodactyles.  The  neck  is  longer  than  in  the  other  Proboscidians,  and  the 
parietal  bones  appear  to  be  narrowed  by  the  approximation  of  the  tem- 
poral fossa,  as  in  the  Rhinocerus.  Almost  nothing  however  is  known  of 
the  structure  of  the  skull. 

The  genera  are  two,  as  follows  : 

Penultimate  molar  unlike  the  last,  with  external  crescent 
and  embracing  ledge Bathmodon. 

Three  molars  alike,  with  two  transverse  crests  not  meet- 
ing within • Metalophodon. 

BATHMODON.     Cope. 
Proceedings  American  Philosopical  Society,  1872,  417. 

This  genus  was  originally  chiefly  distinguished  by  the  dentition  ;  at 
present  many  other  important  peculiarities  are  added.  First,  as  regards 
the  molar  teeth  ;  the  two  transverse  crests  I  find  to  be  separated  (not 
united)  at  their  inner  extremities,  by  a  narrow  fissure.  The  anterior  is 
much  the  longer,  and  is  curved  ;  its  anterior  wall  slopes  steeply  down 
to  the  narrow  cingulum.  The  posterior  is  short,  and  straight,  and  bears 
a  crest.  The  numbers  are  I.  3 ;  C.  1  ;  P.  M.  4  ;  M.  ?  3. 

The  entire  mandible  presents  the  following  dentition  ;  I.  3  ;  C.  1 .  P. 
M.  4 ;  M.  3.  The  incisors  radiate  round  the  narrow  extremity  of  the 
trough-like  symphysis,  and  have  transversely  expanded  crowns.  The 
canine  is  inclined  forwards  and  forms  part  of  the  same  series.  Its  crown 
is  triangular  in  section,  the  outer  face  convex.  In  the  males  it  was 
enormously  enlarged  as  indicated  by  a  symphysis  in  my  possession.  The 
anterior  premolar  approached  the  canine.  The  former  teeth  have  an  ex- 
ternal chevron  directed  inwards,  whose  extero-superior  surface  of  enamel 
is  acute  cordate.  Beside  this  is  a  little  longitudinal  ridge,  which  represents 


31 

another  chevron  of  the  true  molars.  On  the  first  of  the  latter,  both 
chevrons  are  developed,  the  posterior  the  least,  both  with  their  anterior 
ridge  boundaries  lowered  ;  they  sink  entirely  on  the  last  two  molars,  which 
become  thus  two  crested  as  in  those  of  some  Tapiroids  and  the  premolars 
of  Dinotherium. 

The  sternal  segments  are  cylindric  ;  in  one  the  articulations  for  the 
hsetnpophyses  project  laterally,  giving  the  piece  a  T-shaped  form.  The 
atlas  has  a  flat  diaparapophysis,  presenting  its  edges  fore  and  aft ;  the 
arterial  canal  traverses  it  obliquely.  The  coracoid  is  double,  having  a 
tuberosity  on  the  edge  of  the  glenoid  cavity, find  a  prominent  hook  just 
outside  of  it.  The  lumbar  vertebra  are  quite  short.  The  cuneiform 
bone  is  narrow  pyriform,  with  two  triangular  facets  on  one  side,  the 
smaller  being  sublateral ;  and  one  twisted  over  the  other.  The  ungueal 
phalanges  are  very  short,  somewhat  flattened  and  with  the  terminal  por- 
tion transverse  and  rugose  as  in  some  toes  of  Palceytherium. 

In  the  remains  pertaining  to  this  genus  obtained  by  Dr.  Hayden,  there 
are  numerous  individuals  of  apparently  three  species.  Two  of  these  are 
larger  and  one  smaller,  the  latter  in  part  indicated  by  an  individual  with- 
out epiphyses  on  the  lumbar  vertebrae.  It  presents  marked  difference  in 
the  form  of  the  astragalus  atlas,  scapula,  etc. 

a    Larger  species. 

Astragalus  everted  in  front  ;  nearly  as  wide  as  long  ; 
lower  premolars  narrower,  more  elevated  and  rugose ...     B.  radians. 

Lower  premolar  broad,  lower,  and  smooth B.  semicinctus. 

an.     Smaller  species. 

Astragalus  much  wider  than  long,  decurved  in  front. .     B.  latipes. 

BATHMODON  RADIANS.     Cope. 

Proceedings  American  Philosophical  Society,  1872  (February  16),  p. 
418.  Hayden's  Geological  Survey  of  Montana,  1871,  350. 

In  addition  to  the  characters  already  assigned  to  this  species  as  above 
cited,  I  add  the  following  : 

The  apex  of  the  scapula  is  a  massive  flattened  acumination  with  trun- 
cate extremity.  The  spine  is  elevated  and  truncate  next  the  glenoid 
cavity,  which  is  a  wide  oval,  much  produced  at  the  coracoid  margin. 
The  transverse  process  of  the  atlas  is  rounded  distally  and  is  about  as 
long  as  wide  ;  the  surface  for  the  axis  is  directed  obliquely  inwards.  The 
fibula  has  the  inner  sharp  edge  prolonged  to  the  proximal  end  ;  the  form 
of  the  latter  is  much  as  in  Eobasileus.  The  astragalus  is  slightly  concave 
in  both  directions  on  the  trochlear  face,  most  so  antero-posteriorly. 
The  anterior  outline  of  the  same  is  strongly  and  obliquely  convex,  and 
the  surface  is  produced  sideways  into  a  latero-anterior  apex.  The  inner 
malleolar  border  is  thus  very  concave  ;  the  outer  is  gently  convex  with  a 
long  fibular  facet.  The  posterior  margin  concave,  the  inner  tuberosity 


32 

prominent.  The  namcular  facet  is  as  broad  as  long,  and  nearly  sessile, 
being  probably  separated  by  a  groove  from  the  tibial.  The  cuboid  facet 
is  subround,  small  and  sublateral.  The  calcaneal  situated  diagonally 
opposite  each  other.  The  antero-internal  is  twice  as  large  as  the  other, 
is  transverse  and  truncate  internally  by  a  facet  near  the  apex,  at  right 
angles.  The  other  calcaneal  facet  is  subround. 

Measurements. 

M. 
Length  ramus  mandibuli  to  anterior  margin  of  coro- 

noid  process * 0.310 

Length  premolars  and  molars 218    „ 

"       last  molar  crown 040 

Width     "        "  "     030 

"        "        premolar  crown 018 

Length  last  premolar 025 

Width  symphysis  at  canines 045 

Diameter  canines  <5 028 

9 023 

Length  exposed  portion  incisor  2 026 

Width  crown  "       " 0245 

Length  diapophysis  atlas 047 

Width  "  "     056 

"     facet  for  axis 053 

"     glenoid  cavity  scapula  (straight) 086 

Length  coracoid  from  inner  basis 045 

11      proximal  articulation  fibula 027 

"      distal  "  "     042 

Diameter  shaft  "     022 

Total  length  astragalus  (fore  and  aft) 072 

"    width  "         065 

Length  uavicular  facet 045 

Width          "  "     034 

11     cuboid          "     025 

Length     "  "     023 

*  *         anterior  calcaneal  do 040 

Width  "  "        024 

Length  posterior          "         021 

"     fibular  (axial) 043 

The  teeth  are  slightly  rugose,  and  the  inferior  canines  show  a  tendency 
to  imitate  the  form  of  the  incisors  in  a  slight  basal  angular  expan- 
sion of  the  crown.  This  forms  an  approximation  to  the  tapirs.  The 
middle  pair  of  incisors  is  directed  outwards,  is  the  smallest,  and  like 
all  the  others  has  the  roots  much  exposed. 

This  species  was  originally  described  from  teeth  of  the  upper  jaw.  I 
have  since  obtained  the  entire  mandible  (except  the  angles)  taken  out  at 


33 

the  same  place  and  near  the  same  time.  The  size,  color,  etc.,  would 
indicate  that  they  belong  to  the  same  individual.  Accompanying  the  first 
specimens  were  many  bones  of  individuals  of  different  sizes,  which  I 
learn  from  the  the  finder  were  all  taken  from  within  a  short  distance  of 
each  other.  Many  of  them  belong  to  the  same  species,  as  the  jaws  and 
teeth,  and  I  have  described  as  such  those  that  relate  properly  to  them  as 
to  size,  mineral  appearance,  etc. 

The  smaller  specimens  belong  also  to  several  individuals,  and  possibly 
to  more  than  one  species.  I  describe  them  together,  but  regard  the 
astragalus  as  the  primarily  distinctive  bone. 

BATHMODON  SEMICINCTUS.     Cope. 

Proceedings  American  Philosophical  Society,  1872,  p.  420.  Loxolopho- 
don,  semicinctus,  Cope,  1.  c. 

The  tooth  on  which  this  species  was  based  shows  a  near  relation  to  the 
corresponding  one  of  B.  radians. 

BATHMODON  LATIPES.     Cope.     Species  nova. 

Established  on  atlas  axis,  dorsal  and  lumbar  vertebra,  scapula,  hume- 
rus,  phalange,  femur,  astragali,  etc.,  of  a  specimen  found  with  the  B. 
radians. 

The  transverse  process  of  the  atlas  is  stouter  and  less  flattened  at  the 
base  than  in  B.  radians.  The  axis  is  but  little  oblique  and  has  a  low 
obtuse  hypapophysis  below.  Its  form  is  much  as  in  the  larger  species, 
being  rather  elongate,  but  shorter  than  in  Rhinocerus  and  other  Perisso- 
dactyles.  The  dorsals  and  lumbars  are  short  and  plane  ;  the  former  are 
obtusely,  the  latter  acutely  keeled  below.  The  head  of  the  femur  has 
no  ligamentous  fossa.  The  astragalus  is  considerably  broader  than  long, 
the  apex  turned  outwards  in  front  of  the  inner  malleolus,  being  especially 
produced.  The  tibial  face  is  concave  transversely,  and  convex  antero- 
posteriorly  at  the  front,  plane  behind.  There  is  a  posterior  submarginal 
foramen,  which  is  not  bridged  over  in  one  specimen,  producing  a  deep 
notch.  The  navicular  facet  has  considerable  transverse  extent,  and  the 
anterior  side  of  the  bone  is  more  transverse  than  in  B.  radians.  The 
calcaneal  facets  are  diagonally  opposite  to  each  other  ;  the  outer  is  sub- 
round,  the  inner  anterior  narrow  and  transverse.  It  differs  in  the  two 
specimens,  the  perforating  foramen  not  being  bridged  over  in  the  one  (the 
type)  with  the  similar  posterior  interruption  described  above.  This  may 
be  due  to  fracture.  The  only  ungueal  phalange  has  the  articular  face 
not  quite  sessile  on  the  transverse  rugose  free  extremity. 

Measurements. 

M. 

Diameter  diapophysis  atlas  (fore  and  aft) 0.036 

"       axial  facet  of    " 034 

"       centrum  axis  (transverse) 080 

"     (vertical) 037 

Length  "         "to  odontoid 057 


Width  neural  canal  do 030 

(fore  and  aft 040 

Diameter  of  centrum  of  dorsal  J  vertical  (total) 043 

( transverse 051) 

«       neural  arch  of  same  {  S±^;;;.V. ! ! !  IV!     ^ 

i  antero-posterior '041 

"        centrum  of  lumbar  J  vertical  (total) 050 

( transverse 063 

"        head  of  femur 060 

Length  astragalus  fore  and  aft 050 

Width 065 

Length  navicular  facet 049 

Width  "  "    020 

"    cuboid  " 018 

Length     "  "    016 

Width  (fore  and  aft)  anterior  calcaneal 018 

Length  posterior  calcaneal  facet 022 

"      flbular  (axial) 041 

li      terminal  phalange 012 

Width  do  proximally 015 

"    distally 030 


Diameter  glenoid  cavity  scapula  {  ™ 


nr..  .  .  .  . 

From  the  beds  of  the  Green  River  epoch  near  Evanston,  Utah  (now 
Wyoming). 

METALOPHODOK     Cope. 

Proceedings  American  Philosophical  Society,  1872,  p.  542.  (Pub- 
lished September  20th.  ) 

In  distinguishing  this  genus  from  Batlimodon,  I  stated  that  the  differ- 
ences were  in  the  dentition  so  far  as  known  ;  i.  e.  that  the  crests  of  the 
true  molars  are  not  united  internally  and  that  the  premolars  are  two  —  not 
three  —  crested.  I  would  now  add  to  the  characters,  that  there  are  three 
molars  on  each  side,  with  transverse  crests,  which  do  not  unite  at  the 
apex,  except  in  the  case  of  the  anterior,  when  they  are  slightly  connected. 
In  Bathmodon  there  is  but  one  such  tooth,  the  posterior.  The  inner  or 
third  crest  of  the  posterior  premolar  of  that  genus  is  only  a  cingulum, 
and  is  not  probably  a  generic  character. 

METALOPHODON  AKMATUS.     Cope.     Loc.  cit. 

This  species  is  represented  by  the  greater  part  of  the  dental  series  of 
both  jaws,  which  1  took  from  a  decayed  cranium  myself,  and  can  thus  be 
assured  of  their  mutual  relations.  One  of  the  true  molars  at  least, 
belonged  to  the  milk  series,  as  indicated  by  the  unworn  crowns  of  the 
successional  teeth  accompanying.  Some  of  the  premolars  are  but  little 
worn.  Referring  to  my  original  essay  for  the  general  description,  I  append 
exact 


35 

Measurements  of  the  Teeth-. 

M, 

Total  length  of  a  superior  incisor 057 

Length  crown  (inner  face)  superior  incisor 015 

Width         "      (oblique)  "  "      020 

"  "  "  inferior         "      023 

Length       "  (inner  face)  "  "      018 

Width  canine  .030  from  tip 020 

' '      posterior  molar 039 

Length       «  "     028 

Elevation  posterior  crest  do 016 

Width  anterior  true  molar * . .     .035 

"    premolar 028 

Length      "        0215 

".      (first) 016 

Width        «          "    008 

Length       "        (inferior) 024 

Width        "  "         020 

"  penultimate  lower  molar .023 

Length  "  "         "       037 

It  is  not  certain  that  the  last  named  species  of  Bathmodon  does  not  be- 
long to  this  genus.  All  three  are  distinct  from  the  M.  armatus,  the  lat- 
ter though  young,  being  considerably  larger  than  BatJmwdon  latipts, 

APPENDIX. 

The  materials  on  which  the  preceding  determinations  are  based,  were 
obtained  by  the  Geological  Surveys  conducted  during  1871-2,  by  Prof.  F, 
V.  Hayden,  U.  S,  Geologist, 

The  papers  descriptive  of  fossils  from  the  Wyoming  basin  published  by 
the  writer  during  the  jjear  1872,  were  issued  at  the  following  dates  : 

On  Bathmodon,  an  extinct  genus  of  Ungulates,  February  16th. 

On  a  new  genus  of  Pleurodira  from  the  Eocene  of  Wyoming,  July  llth. 

On  the  Tertiary  coals  and  fossils  of  Osino,  Nevada,  July  29th. 

Descriptions  of  some  new  Vertebrate  from  the  Bridger  Group  of  the 
Eocene,  July  29th. 

Second  account  of  new  Vertebrata  from  the  Bridger  Eocene,  August  3d. 

Third  account  of  new  Vertebrate  from  the  Eocene  of  Wyoming  Terri- 
tory, August  7th. 

On  the  existence  of  Dinosauria  in  the  Transition  beds  of  Wyoming, 
near  August  12th, 

Notice  of  Proboscidians  from  the  Eocene  of  Southern  Wyoming, 
August  19th, 

Notices  of  new  Vertebrat.a  from  the  upper  waters  of  Bitter  Creek,  Wy- 
oming Territory,  August  20th, 

Second  notice  of  extinct  Vt'rtttw.tes  from  Bitter  Creek,  Wyoming, 
August  22d. 

On  the  Dentition  of  Metalophodon,  September  2()th- 


On  a,  new  Vertebrate  genus  from  the  northern  part  of  the  Tertiary 
Basin  of  Green  River,  October  12th. 

Descriptions  of  new  Extinct  Reptiles  from  the  Upper  Green  River 
Eocene  Basin,  Wyoming,  October  12th. 

The  above  essays  were  distributed  widely  at  the  above  dates,  except- 
ing that  on  Metalophodon. 

In  an  article  on  Uintatherium  mirabile,  Prof.  O.  C.  Marsh  criticizes  the 
statements  made  in  some  of  the  above  essays,  denying  their  accuracy.  In 
reply  to  such  of  them  as  are  not  frivolous,  I  would  say  that  I  make  no 
corrections  of  them  at  present  (except  one,  which  I  made  prior  to  the 
appearance  of  his  remarks),  but  show  that  his  statements  were  based  on 
species  different  from  those  described  by  me.  These  he  has  either  not 
seen  or  not  studied. 

In  applying  the  law  of  priority  in  nomenclature,  I  have  endeavored 
to  practice  the  rules  adopted  by  the  majority  of  students,  and  which  I 
believe  to  be  founded  in  justice.  They  are  as  follows  : 

(1.)  Priority  reposes  on  date  of  publication  not  on  reading  of  memoirs. 

Note-  What  is  necessary  to  determine  the  time  at  which  a  discovery  of 
scientific  truth  is  made,  is  the  earliest  reliable  evidence  of  such  dis- 
covery. As  verbal  and  written  assertion  cannot  be  preserved  inviolate, 
printing  is  necessary  to  secure  the  record  from  change.  The  earliest 
evidence  of  such  printing  is  that  offered  by  printers,  who  issue  the  work, 
and  any  person  who  receives  it  from  them.  It  is  then  published. 
Ordinary  books  bear  such  date  of  publication,  whether  distributed,  sold, 
or  standing  on  the  author's  shelves. 

(2.)  In  order  that  a  specific  name  be  adopted  it  must  be  associated  with 
a  description  of  the  object  to  which  it  refers. 

Note.  The  necessity  of  this  rule  is  self  evident,  since  the  only  value  of 
scientific  literature  is  to  convey  definite  information,  which  a  name  does 
not.  Moreover  the  worst  description  will  generally  embrace  at  least  one 
peculiarity  of  a  species,  which  will  serve  to  fix  the  name,  but  a  label,  or 
the  specimen  itself,  may  readily  be  lost  or  transposed  in  a  museum. 
Further,  in  writing  descriptions  it  is  necessary  to  introduce  as  many 
points  as  possible,  not  only  to  distinguish  the  species  from  those  already 
known,  but  from  those  which  may  in  future  be  discovered  ;  for  it  is  with 
these  that  difficulties  chiefly  arise. 

(3.)  In  order  that  a  generic  name  be  adopted,  it  also  must  be  accom- 
panied by  a  description. 

Note.  Since  naturalists  differ  to  some  extent  as  to  what  they  term  a 
genus,  some  may  be  disposed  to  doubt  the  expediency  of  this  rule,  but 
its  importance  to  science  appears  to  me  greater  than  in  the  case  of  species. 
In  the  first  place,  scientific  literature  being  designed  for  the  communi- 
cation of  exact  knowledge,  it  is  essential  that  its  words  should  represent 
ideas.  The  genus  is  as  definite  a  mental  conception  as  a  species,  to  the 
scientific,  thinker,  and  in  proposing  a  name,  should  also  express  what  it 


37 

represents  in  his  mind.  Without  such  expression  it  is  safe  to  suppose 
that  no  such  idea  exists  ;  and  if  so,  the  name  should  be  regarded  as  a  cipher 
in  the  literature  of  science. 

That  certainty  as  to  the  limits  and  hence  definition  of  a  genus  is  not 
at  once  attainable,  is  no  objection  to  the  above  rule.  By  study  of  known 
forms  definite  knowledge  of  generic  characters  may  be  attained  by 
proper  analysis.  But  whether  correct  or  not,  a  generic  description 
expresses  something  definite,  and  gives  the  name  a  currency  which 
should  remain  as  a  record  of  honest  work. 

The  evils  which  come  from  the  opposite  course  are  numerous.  They 
are  :  1st.  Names  without  description  are  unintelligible,  and  communicate 
nothing.  3d.  They  serve  to  conceal  the  ignorance  or  incompetency  of 
their  authors.  3d.  If  allowed,  they  open  the  door  to  the  introduction  of 
names  on  geographical  and  stratigraphical  grounds  ;  a  slovenly  pratice, 
indulged  in  by  a  few  paleontologists,  and  properly  denounced  by  Fal- 
coner, as  assuming  at  the  outset  what  it  is  the  design  of  the  science  to 
prove.  The  same  practice  attempted  in  zoology  has  been  utterly  con- 
demned, as  for  example  in  the  case  of  the  System  Reptilium,  published  in 
1843.  Here  pages  of  generic  names  may  be  found,  with  type  species  indi- 
cated, which  have  no  authority  whatever.  4th.  The  practice  lays  the 
science  open  to  the  inroads  of  charlatans  and  scientific  pirates,  who  seek 
to  impose  a  nomenclature  without  the  labor  of  discovering  a  system  or 
describing  its  objects.  5th.  As  the  genus  is  a  more  important  conception 
in  palseontological  science  than  the  species,  it  is  more  important  that  what 
its  name  represents  should  be  clearly  understood,  otherwise  generaliza- 
tions become  impossible  or  incomprehensible. 

(4.)  When  a  supposed  genus  is  found  to  consist  of  several,  and  the 
author  has  stated  what  he  regards  as  the  type  of  the  former,  that 
species  must  retain  the  original  name.  Where  the  type  of  the  original 
genus  is  unknown,  the  original  name  must  attach  to  that  genus  which 
remains,  after  subtraction  of  the  others  found  to  be  embraced  in  the 
original  assemblage. 

Note.  This  rule  is  adopted  as  doing  less  violence  to  long  accepted  views 
and  practice  in  nomenclature  than  any  other.  While  recognizing  the 
work  of  the  original  author,  it  also  preserves  record  of  the  labor  of  those 
who  have  determined  the  true  divisions  with  more  exactitude. 


EXPLANATION  OF  PLATES. 

PI.  1.  LoxolopJwdon  cornutus,  Cope,  profile  natural  size. 
PI.  2.  The  same  from  the  front. 
PI.  3.  Superior  view  of  the  same. 

PI.  4.  Inferior  view. 
Published  March  14th,  1873. 


AmJ>h&>s.Soc  Vol. HZ. 


Plate 


rL  comulux  Cope . 

V6  na£.  Size-. 


Proceed Am.Pkilos.  Soc.  Vol.Hff. 


BlateZ. 


Phiks.  Soc.  Vol.  Jfll. 


f  •'-.• 


loxolop/iodon/  c 


Proceed.Arw.PhJJ0s.  So*  VbfrXni. 


Plate  4. 


'/#  n-a£.  Size. 


